diff options
Diffstat (limited to 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/00-INDEX | 4 | ||||
| -rw-r--r-- | Documentation/networking/bonding.txt | 978 | ||||
| -rw-r--r-- | Documentation/networking/dmfe.txt | 82 | ||||
| -rw-r--r-- | Documentation/networking/fib_trie.txt | 145 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 56 | ||||
| -rw-r--r-- | Documentation/networking/phy.txt | 288 | ||||
| -rw-r--r-- | Documentation/networking/tcp.txt | 69 | ||||
| -rw-r--r-- | Documentation/networking/wanpipe.txt | 622 |
8 files changed, 1228 insertions, 1016 deletions
diff --git a/Documentation/networking/00-INDEX b/Documentation/networking/00-INDEX index 834993d26730..5b01d5cc4e95 100644 --- a/Documentation/networking/00-INDEX +++ b/Documentation/networking/00-INDEX @@ -114,9 +114,7 @@ tuntap.txt vortex.txt - info on using 3Com Vortex (3c590, 3c592, 3c595, 3c597) Ethernet cards. wan-router.txt - - Wan router documentation -wanpipe.txt - - WANPIPE(tm) Multiprotocol WAN Driver for Linux WAN Router + - WAN router documentation wavelan.txt - AT&T GIS (nee NCR) WaveLAN card: An Ethernet-like radio transceiver x25.txt diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index 0bc2ed136a38..24d029455baa 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -1,5 +1,7 @@ - Linux Ethernet Bonding Driver HOWTO + Linux Ethernet Bonding Driver HOWTO + + Latest update: 21 June 2005 Initial release : Thomas Davis <tadavis at lbl.gov> Corrections, HA extensions : 2000/10/03-15 : @@ -11,15 +13,22 @@ Corrections, HA extensions : 2000/10/03-15 : Reorganized and updated Feb 2005 by Jay Vosburgh -Note : ------- +Introduction +============ + + The Linux bonding driver provides a method for aggregating +multiple network interfaces into a single logical "bonded" interface. +The behavior of the bonded interfaces depends upon the mode; generally +speaking, modes provide either hot standby or load balancing services. +Additionally, link integrity monitoring may be performed. -The bonding driver originally came from Donald Becker's beowulf patches for -kernel 2.0. It has changed quite a bit since, and the original tools from -extreme-linux and beowulf sites will not work with this version of the driver. + The bonding driver originally came from Donald Becker's +beowulf patches for kernel 2.0. It has changed quite a bit since, and +the original tools from extreme-linux and beowulf sites will not work +with this version of the driver. -For new versions of the driver, patches for older kernels and the updated -userspace tools, please follow the links at the end of this file. + For new versions of the driver, updated userspace tools, and +who to ask for help, please follow the links at the end of this file. Table of Contents ================= @@ -30,9 +39,13 @@ Table of Contents 3. Configuring Bonding Devices 3.1 Configuration with sysconfig support +3.1.1 Using DHCP with sysconfig +3.1.2 Configuring Multiple Bonds with sysconfig 3.2 Configuration with initscripts support +3.2.1 Using DHCP with initscripts +3.2.2 Configuring Multiple Bonds with initscripts 3.3 Configuring Bonding Manually -3.4 Configuring Multiple Bonds +3.3.1 Configuring Multiple Bonds Manually 5. Querying Bonding Configuration 5.1 Bonding Configuration @@ -56,21 +69,30 @@ Table of Contents 11. Promiscuous mode -12. High Availability Information +12. Configuring Bonding for High Availability 12.1 High Availability in a Single Switch Topology -12.1.1 Bonding Mode Selection for Single Switch Topology -12.1.2 Link Monitoring for Single Switch Topology 12.2 High Availability in a Multiple Switch Topology -12.2.1 Bonding Mode Selection for Multiple Switch Topology -12.2.2 Link Monitoring for Multiple Switch Topology -12.3 Switch Behavior Issues for High Availability +12.2.1 HA Bonding Mode Selection for Multiple Switch Topology +12.2.2 HA Link Monitoring for Multiple Switch Topology + +13. Configuring Bonding for Maximum Throughput +13.1 Maximum Throughput in a Single Switch Topology +13.1.1 MT Bonding Mode Selection for Single Switch Topology +13.1.2 MT Link Monitoring for Single Switch Topology +13.2 Maximum Throughput in a Multiple Switch Topology +13.2.1 MT Bonding Mode Selection for Multiple Switch Topology +13.2.2 MT Link Monitoring for Multiple Switch Topology -13. Hardware Specific Considerations -13.1 IBM BladeCenter +14. Switch Behavior Issues +14.1 Link Establishment and Failover Delays +14.2 Duplicated Incoming Packets -14. Frequently Asked Questions +15. Hardware Specific Considerations +15.1 IBM BladeCenter -15. Resources and Links +16. Frequently Asked Questions + +17. Resources and Links 1. Bonding Driver Installation @@ -86,16 +108,10 @@ the following steps: 1.1 Configure and build the kernel with bonding ----------------------------------------------- - The latest version of the bonding driver is available in the + The current version of the bonding driver is available in the drivers/net/bonding subdirectory of the most recent kernel source -(which is available on http://kernel.org). - - Prior to the 2.4.11 kernel, the bonding driver was maintained -largely outside the kernel tree; patches for some earlier kernels are -available on the bonding sourceforge site, although those patches are -still several years out of date. Most users will want to use either -the most recent kernel from kernel.org or whatever kernel came with -their distro. +(which is available on http://kernel.org). Most users "rolling their +own" will want to use the most recent kernel from kernel.org. Configure kernel with "make menuconfig" (or "make xconfig" or "make config"), then select "Bonding driver support" in the "Network @@ -103,8 +119,8 @@ device support" section. It is recommended that you configure the driver as module since it is currently the only way to pass parameters to the driver or configure more than one bonding device. - Build and install the new kernel and modules, then proceed to -step 2. + Build and install the new kernel and modules, then continue +below to install ifenslave. 1.2 Install ifenslave Control Utility ------------------------------------- @@ -147,9 +163,9 @@ default kernel source include directory. Options for the bonding driver are supplied as parameters to the bonding module at load time. They may be given as command line arguments to the insmod or modprobe command, but are usually specified -in either the /etc/modprobe.conf configuration file, or in a -distro-specific configuration file (some of which are detailed in the -next section). +in either the /etc/modules.conf or /etc/modprobe.conf configuration +file, or in a distro-specific configuration file (some of which are +detailed in the next section). The available bonding driver parameters are listed below. If a parameter is not specified the default value is used. When initially @@ -162,34 +178,34 @@ degradation will occur during link failures. Very few devices do not support at least miimon, so there is really no reason not to use it. Options with textual values will accept either the text name - or, for backwards compatibility, the option value. E.g., - "mode=802.3ad" and "mode=4" set the same mode. +or, for backwards compatibility, the option value. E.g., +"mode=802.3ad" and "mode=4" set the same mode. The parameters are as follows: arp_interval - Specifies the ARP monitoring frequency in milli-seconds. If - ARP monitoring is used in a load-balancing mode (mode 0 or 2), - the switch should be configured in a mode that evenly - distributes packets across all links - such as round-robin. If - the switch is configured to distribute the packets in an XOR + Specifies the ARP link monitoring frequency in milliseconds. + If ARP monitoring is used in an etherchannel compatible mode + (modes 0 and 2), the switch should be configured in a mode + that evenly distributes packets across all links. If the + switch is configured to distribute the packets in an XOR fashion, all replies from the ARP targets will be received on the same link which could cause the other team members to - fail. ARP monitoring should not be used in conjunction with - miimon. A value of 0 disables ARP monitoring. The default + fail. ARP monitoring should not be used in conjunction with + miimon. A value of 0 disables ARP monitoring. The default value is 0. arp_ip_target - Specifies the ip addresses to use when arp_interval is > 0. - These are the targets of the ARP request sent to determine the - health of the link to the targets. Specify these values in - ddd.ddd.ddd.ddd format. Multiple ip adresses must be - seperated by a comma. At least one IP address must be given - for ARP monitoring to function. The maximum number of targets - that can be specified is 16. The default value is no IP - addresses. + Specifies the IP addresses to use as ARP monitoring peers when + arp_interval is > 0. These are the targets of the ARP request + sent to determine the health of the link to the targets. + Specify these values in ddd.ddd.ddd.ddd format. Multiple IP + addresses must be separated by a comma. At least one IP + address must be given for ARP monitoring to function. The + maximum number of targets that can be specified is 16. The + default value is no IP addresses. downdelay @@ -207,11 +223,13 @@ lacp_rate are: slow or 0 - Request partner to transmit LACPDUs every 30 seconds (default) + Request partner to transmit LACPDUs every 30 seconds fast or 1 Request partner to transmit LACPDUs every 1 second + The default is slow. + max_bonds Specifies the number of bonding devices to create for this @@ -221,10 +239,11 @@ max_bonds miimon - Specifies the frequency in milli-seconds that MII link - monitoring will occur. A value of zero disables MII link - monitoring. A value of 100 is a good starting point. The - use_carrier option, below, affects how the link state is + Specifies the MII link monitoring frequency in milliseconds. + This determines how often the link state of each slave is + inspected for link failures. A value of zero disables MII + link monitoring. A value of 100 is a good starting point. + The use_carrier option, below, affects how the link state is determined. See the High Availability section for additional information. The default value is 0. @@ -246,17 +265,31 @@ mode active. A different slave becomes active if, and only if, the active slave fails. The bond's MAC address is externally visible on only one port (network adapter) - to avoid confusing the switch. This mode provides - fault tolerance. The primary option affects the - behavior of this mode. + to avoid confusing the switch. + + In bonding version 2.6.2 or later, when a failover + occurs in active-backup mode, bonding will issue one + or more gratuitous ARPs on the newly active slave. + One gratutious ARP is issued for the bonding master + interface and each VLAN interfaces configured above + it, provided that the interface has at least one IP + address configured. Gratuitous ARPs issued for VLAN + interfaces are tagged with the appropriate VLAN id. + + This mode provides fault tolerance. The primary + option, documented below, affects the behavior of this + mode. balance-xor or 2 - XOR policy: Transmit based on [(source MAC address - XOR'd with destination MAC address) modulo slave - count]. This selects the same slave for each - destination MAC address. This mode provides load - balancing and fault tolerance. + XOR policy: Transmit based on the selected transmit + hash policy. The default policy is a simple [(source + MAC address XOR'd with destination MAC address) modulo + slave count]. Alternate transmit policies may be + selected via the xmit_hash_policy option, described + below. + + This mode provides load balancing and fault tolerance. broadcast or 3 @@ -270,7 +303,17 @@ mode duplex settings. Utilizes all slaves in the active aggregator according to the 802.3ad specification. - Pre-requisites: + Slave selection for outgoing traffic is done according + to the transmit hash policy, which may be changed from + the default simple XOR policy via the xmit_hash_policy + option, documented below. Note that not all transmit + policies may be 802.3ad compliant, particularly in + regards to the packet mis-ordering requirements of + section 43.2.4 of the 802.3ad standard. Differing + peer implementations will have varying tolerances for + noncompliance. + + Prerequisites: 1. Ethtool support in the base drivers for retrieving the speed and duplex of each slave. @@ -333,7 +376,7 @@ mode When a link is reconnected or a new slave joins the bond the receive traffic is redistributed among all - active slaves in the bond by intiating ARP Replies + active slaves in the bond by initiating ARP Replies with the selected mac address to each of the clients. The updelay parameter (detailed below) must be set to a value equal or greater than the switch's @@ -396,6 +439,60 @@ use_carrier 0 will use the deprecated MII / ETHTOOL ioctls. The default value is 1. +xmit_hash_policy + + Selects the transmit hash policy to use for slave selection in + balance-xor and 802.3ad modes. Possible values are: + + layer2 + + Uses XOR of hardware MAC addresses to generate the + hash. The formula is + + (source MAC XOR destination MAC) modulo slave count + + This algorithm will place all traffic to a particular + network peer on the same slave. + + This algorithm is 802.3ad compliant. + + layer3+4 + + This policy uses upper layer protocol information, + when available, to generate the hash. This allows for + traffic to a particular network peer to span multiple + slaves, although a single connection will not span + multiple slaves. + + The formula for unfragmented TCP and UDP packets is + + ((source port XOR dest port) XOR + ((source IP XOR dest IP) AND 0xffff) + modulo slave count + + For fragmented TCP or UDP packets and all other IP + protocol traffic, the source and destination port + information is omitted. For non-IP traffic, the + formula is the same as for the layer2 transmit hash + policy. + + This policy is intended to mimic the behavior of + certain switches, notably Cisco switches with PFC2 as + well as some Foundry and IBM products. + + This algorithm is not fully 802.3ad compliant. A + single TCP or UDP conversation containing both + fragmented and unfragmented packets will see packets + striped across two interfaces. This may result in out + of order delivery. Most traffic types will not meet + this criteria, as TCP rarely fragments traffic, and + most UDP traffic is not involved in extended + conversations. Other implementations of 802.3ad may + or may not tolerate this noncompliance. + + The default value is layer2. This option was added in bonding +version 2.6.3. In earlier versions of bonding, this parameter does +not exist, and the layer2 policy is the only policy. 3. Configuring Bonding Devices @@ -448,8 +545,9 @@ Bonding devices can be managed by hand, however, as follows. slave devices. On SLES 9, this is most easily done by running the yast2 sysconfig configuration utility. The goal is for to create an ifcfg-id file for each slave device. The simplest way to accomplish -this is to configure the devices for DHCP. The name of the -configuration file for each device will be of the form: +this is to configure the devices for DHCP (this is only to get the +file ifcfg-id file created; see below for some issues with DHCP). The +name of the configuration file for each device will be of the form: ifcfg-id-xx:xx:xx:xx:xx:xx @@ -459,7 +557,7 @@ the device's permanent MAC address. Once the set of ifcfg-id-xx:xx:xx:xx:xx:xx files has been created, it is necessary to edit the configuration files for the slave devices (the MAC addresses correspond to those of the slave devices). -Before editing, the file will contain muliple lines, and will look +Before editing, the file will contain multiple lines, and will look something like this: BOOTPROTO='dhcp' @@ -496,16 +594,11 @@ STARTMODE="onboot" BONDING_MASTER="yes" BONDING_MODULE_OPTS="mode=active-backup miimon=100" BONDING_SLAVE0="eth0" -BONDING_SLAVE1="eth1" +BONDING_SLAVE1="bus-pci-0000:06:08.1" Replace the sample BROADCAST, IPADDR, NETMASK and NETWORK values with the appropriate values for your network. - Note that configuring the bonding device with BOOTPROTO='dhcp' -does not work; the scripts attempt to obtain the device address from -DHCP prior to adding any of the slave devices. Without active slaves, -the DHCP requests are not sent to the network. - The STARTMODE specifies when the device is brought online. The possible values are: @@ -531,9 +624,17 @@ for the bonding mode, link monitoring, and so on here. Do not include the max_bonds bonding parameter; this will confuse the configuration system if you have multiple bonding devices. - Finally, supply one BONDING_SLAVEn="ethX" for each slave, -where "n" is an increasing value, one for each slave, and "ethX" is -the name of the slave device (eth0, eth1, etc). + Finally, supply one BONDING_SLAVEn="slave device" for each +slave. where "n" is an increasing value, one for each slave. The +"slave device" is either an interface name, e.g., "eth0", or a device +specifier for the network device. The interface name is easier to +find, but the ethN names are subject to change at boot time if, e.g., +a device early in the sequence has failed. The device specifiers +(bus-pci-0000:06:08.1 in the example above) specify the physical +network device, and will not change unless the device's bus location +changes (for example, it is moved from one PCI slot to another). The +example above uses one of each type for demonstration purposes; most +configurations will choose one or the other for all slave devices. When all configuration files have been modified or created, networking must be restarted for the configuration changes to take @@ -544,7 +645,7 @@ effect. This can be accomplished via the following: Note that the network control script (/sbin/ifdown) will remove the bonding module as part of the network shutdown processing, so it is not necessary to remove the module by hand if, e.g., the -module paramters have changed. +module parameters have changed. Also, at this writing, YaST/YaST2 will not manage bonding devices (they do not show bonding interfaces on its list of network @@ -559,12 +660,37 @@ format can be found in an example ifcfg template file: Note that the template does not document the various BONDING_ settings described above, but does describe many of the other options. +3.1.1 Using DHCP with sysconfig +------------------------------- + + Under sysconfig, configuring a device with BOOTPROTO='dhcp' +will cause it to query DHCP for its IP address information. At this +writing, this does not function for bonding devices; the scripts +attempt to obtain the device address from DHCP prior to adding any of +the slave devices. Without active slaves, the DHCP requests are not +sent to the network. + +3.1.2 Configuring Multiple Bonds with sysconfig +----------------------------------------------- + + The sysconfig network initialization system is capable of +handling multiple bonding devices. All that is necessary is for each +bonding instance to have an appropriately configured ifcfg-bondX file +(as described above). Do not specify the "max_bonds" parameter to any +instance of bonding, as this will confuse sysconfig. If you require +multiple bonding devices with identical parameters, create multiple +ifcfg-bondX files. + + Because the sysconfig scripts supply the bonding module +options in the ifcfg-bondX file, it is not necessary to add them to +the system /etc/modules.conf or /etc/modprobe.conf configuration file. + 3.2 Configuration with initscripts support ------------------------------------------ This section applies to distros using a version of initscripts with bonding support, for example, Red Hat Linux 9 or Red Hat -Enterprise Linux version 3. On these systems, the network +Enterprise Linux version 3 or 4. On these systems, the network initialization scripts have some knowledge of bonding, and can be configured to control bonding devices. @@ -614,10 +740,11 @@ USERCTL=no Be sure to change the networking specific lines (IPADDR, NETMASK, NETWORK and BROADCAST) to match your network configuration. - Finally, it is necessary to edit /etc/modules.conf to load the -bonding module when the bond0 interface is brought up. The following -sample lines in /etc/modules.conf will load the bonding module, and -select its options: + Finally, it is necessary to edit /etc/modules.conf (or +/etc/modprobe.conf, depending upon your distro) to load the bonding +module with your desired options when the bond0 interface is brought +up. The following lines in /etc/modules.conf (or modprobe.conf) will +load the bonding module, and select its options: alias bond0 bonding options bond0 mode=balance-alb miimon=100 @@ -629,6 +756,33 @@ options for your configuration. will restart the networking subsystem and your bond link should be now up and running. +3.2.1 Using DHCP with initscripts +--------------------------------- + + Recent versions of initscripts (the version supplied with +Fedora Core 3 and Red Hat Enterprise Linux 4 is reported to work) do +have support for assigning IP information to bonding devices via DHCP. + + To configure bonding for DHCP, configure it as described +above, except replace the line "BOOTPROTO=none" with "BOOTPROTO=dhcp" +and add a line consisting of "TYPE=Bonding". Note that the TYPE value +is case sensitive. + +3.2.2 Configuring Multiple Bonds with initscripts +------------------------------------------------- + + At this writing, the initscripts package does not directly +support loading the bonding driver multiple times, so the process for +doing so is the same as described in the "Configuring Multiple Bonds +Manually" section, below. + + NOTE: It has been observed that some Red Hat supplied kernels +are apparently unable to rename modules at load time (the "-obonding1" +part). Attempts to pass that option to modprobe will produce an +"Operation not permitted" error. This has been reported on some +Fedora Core kernels, and has been seen on RHEL 4 as well. On kernels +exhibiting this problem, it will be impossible to configure multiple +bonds with differing parameters. 3.3 Configuring Bonding Manually -------------------------------- @@ -638,10 +792,11 @@ scripts (the sysconfig or initscripts package) do not have specific knowledge of bonding. One such distro is SuSE Linux Enterprise Server version 8. - The general methodology for these systems is to place the -bonding module parameters into /etc/modprobe.conf, then add modprobe -and/or ifenslave commands to the system's global init script. The -name of the global init script differs; for sysconfig, it is + The general method for these systems is to place the bonding +module parameters into /etc/modules.conf or /etc/modprobe.conf (as +appropriate for the installed distro), then add modprobe and/or +ifenslave commands to the system's global init script. The name of +the global init script differs; for sysconfig, it is /etc/init.d/boot.local and for initscripts it is /etc/rc.d/rc.local. For example, if you wanted to make a simple bond of two e100 @@ -649,7 +804,7 @@ devices (presumed to be eth0 and eth1), and have it persist across reboots, edit the appropriate file (/etc/init.d/boot.local or /etc/rc.d/rc.local), and add the following: -modprobe bonding -obond0 mode=balance-alb miimon=100 +modprobe bonding mode=balance-alb miimon=100 modprobe e100 ifconfig bond0 192.168.1.1 netmask 255.255.255.0 up ifenslave bond0 eth0 @@ -657,11 +812,7 @@ ifenslave bond0 eth1 Replace the example bonding module parameters and bond0 network configuration (IP address, netmask, etc) with the appropriate -values for your configuration. The above example loads the bonding -module with the name "bond0," this simplifies the naming if multiple -bonding modules are loaded (each successive instance of the module is -given a different name, and the module instance names match the -bonding interface names). +values for your configuration. Unfortunately, this method will not provide support for the ifup and ifdown scripts on the bond devices. To reload the bonding @@ -684,20 +835,23 @@ appropriate device driver modules. For our example above, you can do the following: # ifconfig bond0 down -# rmmod bond0 +# rmmod bonding # rmmod e100 Again, for convenience, it may be desirable to create a script with these commands. -3.4 Configuring Multiple Bonds ------------------------------- +3.3.1 Configuring Multiple Bonds Manually +----------------------------------------- This section contains information on configuring multiple -bonding devices with differing options. If you require multiple -bonding devices, but all with the same options, see the "max_bonds" -module paramter, documented above. +bonding devices with differing options for those systems whose network +initialization scripts lack support for configuring multiple bonds. + + If you require multiple bonding devices, but all with the same +options, you may wish to use the "max_bonds" module parameter, +documented above. To create multiple bonding devices with differing options, it is necessary to load the bonding driver multiple times. Note that @@ -724,11 +878,16 @@ named "bond0" and creates the bond0 device in balance-rr mode with an miimon of 100. The second instance is named "bond1" and creates the bond1 device in balance-alb mode with an miimon of 50. + In some circumstances (typically with older distributions), +the above does not work, and the second bonding instance never sees +its options. In that case, the second options line can be substituted +as follows: + +install bonding1 /sbin/modprobe bonding -obond1 mode=balance-alb miimon=50 + This may be repeated any number of times, specifying a new and -unique name in place of bond0 or bond1 for each instance. +unique name in place of bond1 for each subsequent instance. - When the appropriate module paramters are in place, then -configure bonding according to the instructions for your distro. 5. Querying Bonding Configuration ================================= @@ -846,8 +1005,8 @@ tagged internally by bonding itself. As a result, bonding must self generated packets. For reasons of simplicity, and to support the use of adapters -that can do VLAN hardware acceleration offloding, the bonding -interface declares itself as fully hardware offloaing capable, it gets +that can do VLAN hardware acceleration offloading, the bonding +interface declares itself as fully hardware offloading capable, it gets the add_vid/kill_vid notifications to gather the necessary information, and it propagates those actions to the slaves. In case of mixed adapter types, hardware accelerated tagged packets that @@ -880,7 +1039,7 @@ bond interface: matches the hardware address of the VLAN interfaces. Note that changing a VLAN interface's HW address would set the -underlying device -- i.e. the bonding interface -- to promiscouos +underlying device -- i.e. the bonding interface -- to promiscuous mode, which might not be what you want. @@ -923,7 +1082,7 @@ down or have a problem making it unresponsive to ARP requests. Having an additional target (or several) increases the reliability of the ARP monitoring. - Multiple ARP targets must be seperated by commas as follows: + Multiple ARP targets must be separated by commas as follows: # example options for ARP monitoring with three targets alias bond0 bonding @@ -1045,7 +1204,7 @@ install bonding /sbin/modprobe tg3; /sbin/modprobe e1000; This will, when loading the bonding module, rather than performing the normal action, instead execute the provided command. This command loads the device drivers in the order needed, then calls -modprobe with --ingore-install to cause the normal action to then take +modprobe with --ignore-install to cause the normal action to then take place. Full documentation on this can be found in the modprobe.conf and modprobe manual pages. @@ -1130,14 +1289,14 @@ association. common to enable promiscuous mode on the device, so that all traffic is seen (instead of seeing only traffic destined for the local host). The bonding driver handles promiscuous mode changes to the bonding -master device (e.g., bond0), and propogates the setting to the slave +master device (e.g., bond0), and propagates the setting to the slave devices. For the balance-rr, balance-xor, broadcast, and 802.3ad modes, -the promiscuous mode setting is propogated to all slaves. +the promiscuous mode setting is propagated to all slaves. For the active-backup, balance-tlb and balance-alb modes, the -promiscuous mode setting is propogated only to the active slave. +promiscuous mode setting is propagated only to the active slave. For balance-tlb mode, the active slave is the slave currently receiving inbound traffic. @@ -1148,46 +1307,182 @@ sending to peers that are unassigned or if the load is unbalanced. For the active-backup, balance-tlb and balance-alb modes, when the active slave changes (e.g., due to a link failure), the -promiscuous setting will be propogated to the new active slave. +promiscuous setting will be propagated to the new active slave. -12. High Availability Information -================================= +12. Configuring Bonding for High Availability +============================================= High Availability refers to configurations that provide maximum network availability by having redundant or backup devices, -links and switches between the host and the rest of the world. - - There are currently two basic methods for configuring to -maximize availability. They are dependent on the network topology and -the primary goal of the configuration, but in general, a configuration -can be optimized for maximum available bandwidth, or for maximum -network availability. +links or switches between the host and the rest of the world. The +goal is to provide the maximum availability of network connectivity +(i.e., the network always works), even though other configurations +could provide higher throughput. 12.1 High Availability in a Single Switch Topology -------------------------------------------------- - If two hosts (or a host and a switch) are directly connected -via multiple physical links, then there is no network availability -penalty for optimizing for maximum bandwidth: there is only one switch -(or peer), so if it fails, you have no alternative access to fail over -to. + If two hosts (or a host and a single switch) are directly +connected via multiple physical links, then there is no availability +penalty to optimizing for maximum bandwidth. In this case, there is +only one switch (or peer), so if it fails, there is no alternative +access to fail over to. Additionally, the bonding load balance modes +support link monitoring of their members, so if individual links fail, +the load will be rebalanced across the remaining devices. + + See Section 13, "Configuring Bonding for Maximum Throughput" +for information on configuring bonding with one peer device. + +12.2 High Availability in a Multiple Switch Topology +---------------------------------------------------- + + With multiple switches, the configuration of bonding and the +network changes dramatically. In multiple switch topologies, there is +a trade off between network availability and usable bandwidth. + + Below is a sample network, configured to maximize the +availability of the network: -Example 1 : host to switch (or other host) + | | + |port3 port3| + +-----+----+ +-----+----+ + | |port2 ISL port2| | + | switch A +--------------------------+ switch B | + | | | | + +-----+----+ +-----++---+ + |port1 port1| + | +-------+ | + +-------------+ host1 +---------------+ + eth0 +-------+ eth1 - +----------+ +----------+ - | |eth0 eth0| switch | - | Host A +--------------------------+ or | - | +--------------------------+ other | - | |eth1 eth1| host | - +----------+ +----------+ + In this configuration, there is a link between the two +switches (ISL, or inter switch link), and multiple ports connecting to +the outside world ("port3" on each switch). There is no technical +reason that this could not be extended to a third switch. +12.2.1 HA Bonding Mode Selection for Multiple Switch Topology +------------------------------------------------------------- -12.1.1 Bonding Mode Selection for single switch topology --------------------------------------------------------- + In a topology such as the example above, the active-backup and +broadcast modes are the only useful bonding modes when optimizing for +availability; the other modes require all links to terminate on the +same peer for them to behave rationally. + +active-backup: This is generally the preferred mode, particularly if + the switches have an ISL and play together well. If the + network configuration is such that one switch is specifically + a backup switch (e.g., has lower capacity, higher cost, etc), + then the primary option can be used to insure that the + preferred link is always used when it is available. + +broadcast: This mode is really a special purpose mode, and is suitable + only for very specific needs. For example, if the two + switches are not connected (no ISL), and the networks beyond + them are totally independent. In this case, if it is + necessary for some specific one-way traffic to reach both + independent networks, then the broadcast mode may be suitable. + +12.2.2 HA Link Monitoring Selection for Multiple Switch Topology +---------------------------------------------------------------- + + The choice of link monitoring ultimately depends upon your +switch. If the switch can reliably fail ports in response to other +failures, then either the MII or ARP monitors should work. For +example, in the above example, if the "port3" link fails at the remote +end, the MII monitor has no direct means to detect this. The ARP +monitor could be configured with a target at the remote end of port3, +thus detecting that failure without switch support. + + In general, however, in a multiple switch topology, the ARP +monitor can provide a higher level of reliability in detecting end to +end connectivity failures (which may be caused by the failure of any +individual component to pass traffic for any reason). Additionally, +the ARP monitor should be configured with multiple targets (at least +one for each switch in the network). This will insure that, +regardless of which switch is active, the ARP monitor has a suitable +target to query. + + +13. Configuring Bonding for Maximum Throughput +============================================== + +13.1 Maximizing Throughput in a Single Switch Topology +------------------------------------------------------ + + In a single switch configuration, the best method to maximize +throughput depends upon the application and network environment. The +various load balancing modes each have strengths and weaknesses in +different environments, as detailed below. + + For this discussion, we will break down the topologies into +two categories. Depending upon the destination of most traffic, we +categorize them into either "gatewayed" or "local" configurations. + + In a gatewayed configuration, the "switch" is acting primarily +as a router, and the majority of traffic passes through this router to +other networks. An example would be the following: + + + +----------+ +----------+ + | |eth0 port1| | to other networks + | Host A +---------------------+ router +-------------------> + | +---------------------+ | Hosts B and C are out + | |eth1 port2| | here somewhere + +----------+ +----------+ + + The router may be a dedicated router device, or another host +acting as a gateway. For our discussion, the important point is that +the majority of traffic from Host A will pass through the router to +some other network before reaching its final destination. + + In a gatewayed network configuration, although Host A may +communicate with many other systems, all of its traffic will be sent +and received via one other peer on the local network, the router. + + Note that the case of two systems connected directly via +multiple physical links is, for purposes of configuring bonding, the +same as a gatewayed configuration. In that case, it happens that all +traffic is destined for the "gateway" itself, not some other network +beyond the gateway. + + In a local configuration, the "switch" is acting primarily as +a switch, and the majority of traffic passes through this switch to +reach other stations on the same network. An example would be the +following: + + +----------+ +----------+ +--------+ + | |eth0 port1| +-------+ Host B | + | Host A +------------+ switch |port3 +--------+ + | +------------+ | +--------+ + | |eth1 port2| +------------------+ Host C | + +----------+ +----------+port4 +--------+ + + + Again, the switch may be a dedicated switch device, or another +host acting as a gateway. For our discussion, the important point is +that the majority of traffic from Host A is destined for other hosts +on the same local network (Hosts B and C in the above example). + + In summary, in a gatewayed configuration, traffic to and from +the bonded device will be to the same MAC level peer on the network +(the gateway itself, i.e., the router), regardless of its final +destination. In a local configuration, traffic flows directly to and +from the final destinations, thus, each destination (Host B, Host C) +will be addressed directly by their individual MAC addresses. + + This distinction between a gatewayed and a local network +configuration is important because many of the load balancing modes +available use the MAC addresses of the local network source and +destination to make load balancing decisions. The behavior of each +mode is described below. + + +13.1.1 MT Bonding Mode Selection for Single Switch Topology +----------------------------------------------------------- This configuration is the easiest to set up and to understand, although you will have to decide which bonding mode best suits your -needs. The tradeoffs for each mode are detailed below: +needs. The trade offs for each mode are detailed below: balance-rr: This mode is the only mode that will permit a single TCP/IP connection to stripe traffic across multiple @@ -1206,6 +1501,23 @@ balance-rr: This mode is the only mode that will permit a single interface's worth of throughput, even after adjusting tcp_reordering. + Note that this out of order delivery occurs when both the + sending and receiving systems are utilizing a multiple + interface bond. Consider a configuration in which a + balance-rr bond feeds into a single higher capacity network + channel (e.g., multiple 100Mb/sec ethernets feeding a single + gigabit ethernet via an etherchannel capable switch). In this + configuration, traffic sent from the multiple 100Mb devices to + a destination connected to the gigabit device will not see + packets out of order. However, traffic sent from the gigabit + device to the multiple 100Mb devices may or may not see + traffic out of order, depending upon the balance policy of the + switch. Many switches do not support any modes that stripe + traffic (instead choosing a port based upon IP or MAC level + addresses); for those devices, traffic flowing from the + gigabit device to the many 100Mb devices will only utilize one + interface. + If you are utilizing protocols other than TCP/IP, UDP for example, and your application can tolerate out of order delivery, then this mode can allow for single stream datagram @@ -1220,16 +1532,21 @@ active-backup: There is not much advantage in this network topology to connected to the same peer as the primary. In this case, a load balancing mode (with link monitoring) will provide the same level of network availability, but with increased - available bandwidth. On the plus side, it does not require - any configuration of the switch. + available bandwidth. On the plus side, active-backup mode + does not require any configuration of the switch, so it may + have value if the hardware available does not support any of + the load balance modes. balance-xor: This mode will limit traffic such that packets destined for specific peers will always be sent over the same interface. Since the destination is determined by the MAC - addresses involved, this may be desirable if you have a large - network with many hosts. It is likely to be suboptimal if all - your traffic is passed through a single router, however. As - with balance-rr, the switch ports need to be configured for + addresses involved, this mode works best in a "local" network + configuration (as described above), with destinations all on + the same local network. This mode is likely to be suboptimal + if all your traffic is passed through a single router (i.e., a + "gatewayed" network configuration, as described above). + + As with balance-rr, the switch ports need to be configured for "etherchannel" or "trunking." broadcast: Like active-backup, there is not much advantage to this @@ -1241,122 +1558,131 @@ broadcast: Like active-backup, there is not much advantage to this protocol includes automatic configuration of the aggregates, so minimal manual configuration of the switch is needed (typically only to designate that some set of devices is - usable for 802.3ad). The 802.3ad standard also mandates that - frames be delivered in order (within certain limits), so in - general single connections will not see misordering of + available for 802.3ad). The 802.3ad standard also mandates + that frames be delivered in order (within certain limits), so + in general single connections will not see misordering of packets. The 802.3ad mode does have some drawbacks: the standard mandates that all devices in the aggregate operate at the same speed and duplex. Also, as with all bonding load balance modes other than balance-rr, no single connection will be able to utilize more than a single interface's worth of - bandwidth. Additionally, the linux bonding 802.3ad - implementation distributes traffic by peer (using an XOR of - MAC addresses), so in general all traffic to a particular - destination will use the same interface. Finally, the 802.3ad - mode mandates the use of the MII monitor, therefore, the ARP - monitor is not available in this mode. - -balance-tlb: This mode is also a good choice for this type of - topology. It has no special switch configuration - requirements, and balances outgoing traffic by peer, in a - vaguely intelligent manner (not a simple XOR as in balance-xor - or 802.3ad mode), so that unlucky MAC addresses will not all - "bunch up" on a single interface. Interfaces may be of - differing speeds. On the down side, in this mode all incoming - traffic arrives over a single interface, this mode requires - certain ethtool support in the network device driver of the - slave interfaces, and the ARP monitor is not available. - -balance-alb: This mode is everything that balance-tlb is, and more. It - has all of the features (and restrictions) of balance-tlb, and - will also balance incoming traffic from peers (as described in - the Bonding Module Options section, above). The only extra - down side to this mode is that the network device driver must - support changing the hardware address while the device is - open. - -12.1.2 Link Monitoring for Single Switch Topology -------------------------------------------------- + bandwidth. + + Additionally, the linux bonding 802.3ad implementation + distributes traffic by peer (using an XOR of MAC addresses), + so in a "gatewayed" configuration, all outgoing traffic will + generally use the same device. Incoming traffic may also end + up on a single device, but that is dependent upon the + balancing policy of the peer's 8023.ad implementation. In a + "local" configuration, traffic will be distributed across the + devices in the bond. + + Finally, the 802.3ad mode mandates the use of the MII monitor, + therefore, the ARP monitor is not available in this mode. + +balance-tlb: The balance-tlb mode balances outgoing traffic by peer. + Since the balancing is done according to MAC address, in a + "gatewayed" configuration (as described above), this mode will + send all traffic across a single device. However, in a + "local" network configuration, this mode balances multiple + local network peers across devices in a vaguely intelligent + manner (not a simple XOR as in balance-xor or 802.3ad mode), + so that mathematically unlucky MAC addresses (i.e., ones that + XOR to the same value) will not all "bunch up" on a single + interface. + + Unlike 802.3ad, interfaces may be of differing speeds, and no + special switch configuration is required. On the down side, + in this mode all incoming traffic arrives over a single + interface, this mode requires certain ethtool support in the + network device driver of the slave interfaces, and the ARP + monitor is not available. + +balance-alb: This mode is everything that balance-tlb is, and more. + It has all of the features (and restrictions) of balance-tlb, + and will also balance incoming traffic from local network + peers (as described in the Bonding Module Options section, + above). + + The only additional down side to this mode is that the network + device driver must support changing the hardware address while + the device is open. + +13.1.2 MT Link Monitoring for Single Switch Topology +---------------------------------------------------- The choice of link monitoring may largely depend upon which mode you choose to use. The more advanced load balancing modes do not support the use of the ARP monitor, and are thus restricted to using -the MII monitor (which does not provide as high a level of assurance -as the ARP monitor). - - -12.2 High Availability in a Multiple Switch Topology ----------------------------------------------------- - - With multiple switches, the configuration of bonding and the -network changes dramatically. In multiple switch topologies, there is -a tradeoff between network availability and usable bandwidth. - - Below is a sample network, configured to maximize the -availability of the network: - - | | - |port3 port3| - +-----+----+ +-----+----+ - | |port2 ISL port2| | - | switch A +--------------------------+ switch B | - | | | | - +-----+----+ +-----++---+ - |port1 port1| - | +-------+ | - +-------------+ host1 +---------------+ - eth0 +-------+ eth1 - - In this configuration, there is a link between the two -switches (ISL, or inter switch link), and multiple ports connecting to -the outside world ("port3" on each switch). There is no technical -reason that this could not be extended to a third switch. - -12.2.1 Bonding Mode Selection for Multiple Switch Topology ----------------------------------------------------------- - - In a topology such as this, the active-backup and broadcast -modes are the only useful bonding modes; the other modes require all -links to terminate on the same peer for them to behave rationally. - -active-backup: This is generally the preferred mode, particularly if - the switches have an ISL and play together well. If the - network configuration is such that one switch is specifically - a backup switch (e.g., has lower capacity, higher cost, etc), - then the primary option can be used to insure that the - preferred link is always used when it is available. - -broadcast: This mode is really a special purpose mode, and is suitable - only for very specific needs. For example, if the two - switches are not connected (no ISL), and the networks beyond - them are totally independant. In this case, if it is - necessary for some specific one-way traffic to reach both - independent networks, then the broadcast mode may be suitable. - -12.2.2 Link Monitoring Selection for Multiple Switch Topology +the MII monitor (which does not provide as high a level of end to end +assurance as the ARP monitor). + +13.2 Maximum Throughput in a Multiple Switch Topology +----------------------------------------------------- + + Multiple switches may be utilized to optimize for throughput +when they are configured in parallel as part of an isolated network +between two or more systems, for example: + + +-----------+ + | Host A | + +-+---+---+-+ + | | | + +--------+ | +---------+ + | | | + +------+---+ +-----+----+ +-----+----+ + | Switch A | | Switch B | | Switch C | + +------+---+ +-----+----+ +-----+----+ + | | | + +--------+ | +---------+ + | | | + +-+---+---+-+ + | Host B | + +-----------+ + + In this configuration, the switches are isolated from one +another. One reason to employ a topology such as this is for an +isolated network with many hosts (a cluster configured for high +performance, for example), using multiple smaller switches can be more +cost effective than a single larger switch, e.g., on a network with 24 +hosts, three 24 port switches can be significantly less expensive than +a single 72 port switch. + + If access beyond the network is required, an individual host +can be equipped with an additional network device connected to an +external network; this host then additionally acts as a gateway. + +13.2.1 MT Bonding Mode Selection for Multiple Switch Topology ------------------------------------------------------------- - The choice of link monitoring ultimately depends upon your -switch. If the switch can reliably fail ports in response to other -failures, then either the MII or ARP monitors should work. For -example, in the above example, if the "port3" link fails at the remote -end, the MII monitor has no direct means to detect this. The ARP -monitor could be configured with a target at the remote end of port3, -thus detecting that failure without switch support. + In actual practice, the bonding mode typically employed in +configurations of this type is balance-rr. Historically, in this +network configuration, the usual caveats about out of order packet +delivery are mitigated by the use of network adapters that do not do +any kind of packet coalescing (via the use of NAPI, or because the +device itself does not generate interrupts until some number of +packets has arrived). When employed in this fashion, the balance-rr +mode allows individual connections between two hosts to effectively +utilize greater than one interface's bandwidth. - In general, however, in a multiple switch topology, the ARP -monitor can provide a higher level of reliability in detecting link -failures. Additionally, it should be configured with multiple targets -(at least one for each switch in the network). This will insure that, -regardless of which switch is active, the ARP monitor has a suitable -target to query. +13.2.2 MT Link Monitoring for Multiple Switch Topology +------------------------------------------------------ + Again, in actual practice, the MII monitor is most often used +in this configuration, as performance is given preference over +availability. The ARP monitor will function in this topology, but its +advantages over the MII monitor are mitigated by the volume of probes +needed as the number of systems involved grows (remember that each +host in the network is configured with bonding). -12.3 Switch Behavior Issues for High Availability -------------------------------------------------- +14. Switch Behavior Issues +========================== - You may encounter issues with the timing of link up and down -reporting by the switch. +14.1 Link Establishment and Failover Delays +------------------------------------------- + + Some switches exhibit undesirable behavior with regard to the +timing of link up and down reporting by the switch. First, when a link comes up, some switches may indicate that the link is up (carrier available), but not pass traffic over the @@ -1370,30 +1696,70 @@ relevant interface(s). Second, some switches may "bounce" the link state one or more times while a link is changing state. This occurs most commonly while the switch is initializing. Again, an appropriate updelay value may -help, but note that if all links are down, then updelay is ignored -when any link becomes active (the slave closest to completing its -updelay is chosen). +help. Note that when a bonding interface has no active links, the -driver will immediately reuse the first link that goes up, even if -updelay parameter was specified. If there are slave interfaces -waiting for the updelay timeout to expire, the interface that first -went into that state will be immediately reused. This reduces down -time of the network if the value of updelay has been overestimated. +driver will immediately reuse the first link that goes up, even if the +updelay parameter has been specified (the updelay is ignored in this +case). If there are slave interfaces waiting for the updelay timeout +to expire, the interface that first went into that state will be +immediately reused. This reduces down time of the network if the +value of updelay has been overestimated, and since this occurs only in +cases with no connectivity, there is no additional penalty for +ignoring the updelay. In addition to the concerns about switch timings, if your switches take a long time to go into backup mode, it may be desirable to not activate a backup interface immediately after a link goes down. Failover may be delayed via the downdelay bonding module option. -13. Hardware Specific Considerations +14.2 Duplicated Incoming Packets +-------------------------------- + + It is not uncommon to observe a short burst of duplicated +traffic when the bonding device is first used, or after it has been +idle for some period of time. This is most easily observed by issuing +a "ping" to some other host on the network, and noticing that the +output from ping flags duplicates (typically one per slave). + + For example, on a bond in active-backup mode with five slaves +all connected to one switch, the output may appear as follows: + +# ping -n 10.0.4.2 +PING 10.0.4.2 (10.0.4.2) from 10.0.3.10 : 56(84) bytes of data. +64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.7 ms +64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!) +64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!) +64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!) +64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!) +64 bytes from 10.0.4.2: icmp_seq=2 ttl=64 time=0.216 ms +64 bytes from 10.0.4.2: icmp_seq=3 ttl=64 time=0.267 ms +64 bytes from 10.0.4.2: icmp_seq=4 ttl=64 time=0.222 ms + + This is not due to an error in the bonding driver, rather, it +is a side effect of how many switches update their MAC forwarding +tables. Initially, the switch does not associate the MAC address in +the packet with a particular switch port, and so it may send the +traffic to all ports until its MAC forwarding table is updated. Since +the interfaces attached to the bond may occupy multiple ports on a +single switch, when the switch (temporarily) floods the traffic to all +ports, the bond device receives multiple copies of the same packet +(one per slave device). + + The duplicated packet behavior is switch dependent, some +switches exhibit this, and some do not. On switches that display this +behavior, it can be induced by clearing the MAC forwarding table (on +most Cisco switches, the privileged command "clear mac address-table +dynamic" will accomplish this). + +15. Hardware Specific Considerations ==================================== This section contains additional information for configuring bonding on specific hardware platforms, or for interfacing bonding with particular switches or other devices. -13.1 IBM BladeCenter +15.1 IBM BladeCenter -------------------- This applies to the JS20 and similar systems. @@ -1407,12 +1773,12 @@ JS20 network adapter information -------------------------------- All JS20s come with two Broadcom Gigabit Ethernet ports -integrated on the planar. In the BladeCenter chassis, the eth0 port -of all JS20 blades is hard wired to I/O Module #1; similarly, all eth1 -ports are wired to I/O Module #2. An add-on Broadcom daughter card -can be installed on a JS20 to provide two more Gigabit Ethernet ports. -These ports, eth2 and eth3, are wired to I/O Modules 3 and 4, -respectively. +integrated on the planar (that's "motherboard" in IBM-speak). In the +BladeCenter chassis, the eth0 port of all JS20 blades is hard wired to +I/O Module #1; similarly, all eth1 ports are wired to I/O Module #2. +An add-on Broadcom daughter card can be installed on a JS20 to provide +two more Gigabit Ethernet ports. These ports, eth2 and eth3, are +wired to I/O Modules 3 and 4, respectively. Each I/O Module may contain either a switch or a passthrough module (which allows ports to be directly connected to an external @@ -1432,29 +1798,30 @@ BladeCenter networking configuration of ways, this discussion will be confined to describing basic configurations. - Normally, Ethernet Switch Modules (ESM) are used in I/O + Normally, Ethernet Switch Modules (ESMs) are used in I/O modules 1 and 2. In this configuration, the eth0 and eth1 ports of a JS20 will be connected to different internal switches (in the respective I/O modules). - An optical passthru module (OPM) connects the I/O module -directly to an external switch. By using OPMs in I/O module #1 and -#2, the eth0 and eth1 interfaces of a JS20 can be redirected to the -outside world and connected to a common external switch. - - Depending upon the mix of ESM and OPM modules, the network -will appear to bonding as either a single switch topology (all OPM -modules) or as a multiple switch topology (one or more ESM modules, -zero or more OPM modules). It is also possible to connect ESM modules -together, resulting in a configuration much like the example in "High -Availability in a multiple switch topology." - -Requirements for specifc modes ------------------------------- - - The balance-rr mode requires the use of OPM modules for -devices in the bond, all connected to an common external switch. That -switch must be configured for "etherchannel" or "trunking" on the + A passthrough module (OPM or CPM, optical or copper, +passthrough module) connects the I/O module directly to an external +switch. By using PMs in I/O module #1 and #2, the eth0 and eth1 +interfaces of a JS20 can be redirected to the outside world and +connected to a common external switch. + + Depending upon the mix of ESMs and PMs, the network will +appear to bonding as either a single switch topology (all PMs) or as a +multiple switch topology (one or more ESMs, zero or more PMs). It is +also possible to connect ESMs together, resulting in a configuration +much like the example in "High Availability in a Multiple Switch +Topology," above. + +Requirements for specific modes +------------------------------- + + The balance-rr mode requires the use of passthrough modules +for devices in the bond, all connected to an common external switch. +That switch must be configured for "etherchannel" or "trunking" on the appropriate ports, as is usual for balance-rr. The balance-alb and balance-tlb modes will function with @@ -1484,17 +1851,18 @@ connected to the JS20 system. Other concerns -------------- - The Serial Over LAN link is established over the primary + The Serial Over LAN (SoL) link is established over the primary ethernet (eth0) only, therefore, any loss of link to eth0 will result in losing your SoL connection. It will not fail over with other -network traffic. +network traffic, as the SoL system is beyond the control of the +bonding driver. It may be desirable to disable spanning tree on the switch (either the internal Ethernet Switch Module, or an external switch) to -avoid fail-over delays issues when using bonding. +avoid fail-over delay issues when using bonding. -14. Frequently Asked Questions +16. Frequently Asked Questions ============================== 1. Is it SMP safe? @@ -1505,8 +1873,8 @@ The new driver was designed to be SMP safe from the start. 2. What type of cards will work with it? Any Ethernet type cards (you can even mix cards - a Intel -EtherExpress PRO/100 and a 3com 3c905b, for example). They need not -be of the same speed. +EtherExpress PRO/100 and a 3com 3c905b, for example). For most modes, +devices need not be of the same speed. 3. How many bonding devices can I have? @@ -1524,11 +1892,12 @@ system. disabled. The active-backup mode will fail over to a backup link, and other modes will ignore the failed link. The link will continue to be monitored, and should it recover, it will rejoin the bond (in whatever -manner is appropriate for the mode). See the section on High -Availability for additional information. +manner is appropriate for the mode). See the sections on High +Availability and the documentation for each mode for additional +information. Link monitoring can be enabled via either the miimon or -arp_interval paramters (described in the module paramters section, +arp_interval parameters (described in the module parameters section, above). In general, miimon monitors the carrier state as sensed by the underlying network device, and the arp monitor (arp_interval) monitors connectivity to another host on the local network. @@ -1536,7 +1905,7 @@ monitors connectivity to another host on the local network. If no link monitoring is configured, the bonding driver will be unable to detect link failures, and will assume that all links are always available. This will likely result in lost packets, and a -resulting degredation of performance. The precise performance loss +resulting degradation of performance. The precise performance loss depends upon the bonding mode and network configuration. 6. Can bonding be used for High Availability? @@ -1550,12 +1919,12 @@ depends upon the bonding mode and network configuration. In the basic balance modes (balance-rr and balance-xor), it works with any system that supports etherchannel (also called trunking). Most managed switches currently available have such -support, and many unmananged switches as well. +support, and many unmanaged switches as well. The advanced balance modes (balance-tlb and balance-alb) do not have special switch requirements, but do need device drivers that support specific features (described in the appropriate section under -module paramters, above). +module parameters, above). In 802.3ad mode, it works with with systems that support IEEE 802.3ad Dynamic Link Aggregation. Most managed and many unmanaged @@ -1565,17 +1934,19 @@ switches currently available support 802.3ad. 8. Where does a bonding device get its MAC address from? - If not explicitly configured with ifconfig, the MAC address of -the bonding device is taken from its first slave device. This MAC -address is then passed to all following slaves and remains persistent -(even if the the first slave is removed) until the bonding device is -brought down or reconfigured. + If not explicitly configured (with ifconfig or ip link), the +MAC address of the bonding device is taken from its first slave +device. This MAC address is then passed to all following slaves and +remains persistent (even if the the first slave is removed) until the +bonding device is brought down or reconfigured. If you wish to change the MAC address, you can set it with -ifconfig: +ifconfig or ip link: # ifconfig bond0 hw ether 00:11:22:33:44:55 +# ip link set bond0 address 66:77:88:99:aa:bb + The MAC address can be also changed by bringing down/up the device and then changing its slaves (or their order): @@ -1591,23 +1962,28 @@ from the bond (`ifenslave -d bond0 eth0'). The bonding driver will then restore the MAC addresses that the slaves had before they were enslaved. -15. Resources and Links +16. Resources and Links ======================= The latest version of the bonding driver can be found in the latest version of the linux kernel, found on http://kernel.org +The latest version of this document can be found in either the latest +kernel source (named Documentation/networking/bonding.txt), or on the +bonding sourceforge site: + +http://www.sourceforge.net/projects/bonding + Discussions regarding the bonding driver take place primarily on the bonding-devel mailing list, hosted at sourceforge.net. If you have -questions or problems, post them to the list. +questions or problems, post them to the list. The list address is: bonding-devel@lists.sourceforge.net -https://lists.sourceforge.net/lists/listinfo/bonding-devel - -There is also a project site on sourceforge. + The administrative interface (to subscribe or unsubscribe) can +be found at: -http://www.sourceforge.net/projects/bonding +https://lists.sourceforge.net/lists/listinfo/bonding-devel Donald Becker's Ethernet Drivers and diag programs may be found at : - http://www.scyld.com/network/ diff --git a/Documentation/networking/dmfe.txt b/Documentation/networking/dmfe.txt index c0e8398674ef..046363552d09 100644 --- a/Documentation/networking/dmfe.txt +++ b/Documentation/networking/dmfe.txt @@ -1,59 +1,65 @@ - dmfe.c: Version 1.28 01/18/2000 +Davicom DM9102(A)/DM9132/DM9801 fast ethernet driver for Linux. - A Davicom DM9102(A)/DM9132/DM9801 fast ethernet driver for Linux. - Copyright (C) 1997 Sten Wang +This program is free software; you can redistribute it and/or +modify it under the terms of the GNU General Public License +as published by the Free Software Foundation; either version 2 +of the License, or (at your option) any later version. - This program is free software; you can redistribute it and/or - modify it under the terms of the GNU General Public License - as published by the Free Software Foundation; either version 2 - of the License, or (at your option) any later version. +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. +This driver provides kernel support for Davicom DM9102(A)/DM9132/DM9801 ethernet cards ( CNET +10/100 ethernet cards uses Davicom chipset too, so this driver supports CNET cards too ).If you +didn't compile this driver as a module, it will automatically load itself on boot and print a +line similar to : - A. Compiler command: + dmfe: Davicom DM9xxx net driver, version 1.36.4 (2002-01-17) - A-1: For normal single or multiple processor kernel - "gcc -DMODULE -D__KERNEL__ -I/usr/src/linux/net/inet -Wall - -Wstrict-prototypes -O6 -c dmfe.c" +If you compiled this driver as a module, you have to load it on boot.You can load it with command : - A-2: For single or multiple processor with kernel module version function - "gcc -DMODULE -DMODVERSIONS -D__KERNEL__ -I/usr/src/linux/net/inet - -Wall -Wstrict-prototypes -O6 -c dmfe.c" + insmod dmfe +This way it will autodetect the device mode.This is the suggested way to load the module.Or you can pass +a mode= setting to module while loading, like : - B. The following steps teach you how to activate a DM9102 board: + insmod dmfe mode=0 # Force 10M Half Duplex + insmod dmfe mode=1 # Force 100M Half Duplex + insmod dmfe mode=4 # Force 10M Full Duplex + insmod dmfe mode=5 # Force 100M Full Duplex - 1. Used the upper compiler command to compile dmfe.c +Next you should configure your network interface with a command similar to : - 2. Insert dmfe module into kernel - "insmod dmfe" ;;Auto Detection Mode (Suggest) - "insmod dmfe mode=0" ;;Force 10M Half Duplex - "insmod dmfe mode=1" ;;Force 100M Half Duplex - "insmod dmfe mode=4" ;;Force 10M Full Duplex - "insmod dmfe mode=5" ;;Force 100M Full Duplex + ifconfig eth0 172.22.3.18 + ^^^^^^^^^^^ + Your IP Adress - 3. Config a dm9102 network interface - "ifconfig eth0 172.22.3.18" - ^^^^^^^^^^^ Your IP address +Then you may have to modify the default routing table with command : - 4. Activate the IP routing table. For some distributions, it is not - necessary. You can type "route" to check. + route add default eth0 - "route add default eth0" +Now your ethernet card should be up and running. - 5. Well done. Your DM9102 adapter is now activated. +TODO: - C. Object files description: - 1. dmfe_rh61.o: For Redhat 6.1 +Implement pci_driver::suspend() and pci_driver::resume() power management methods. +Check on 64 bit boxes. +Check and fix on big endian boxes. +Test and make sure PCI latency is now correct for all cases. - If you can make sure your kernel version, you can rename - to dmfe.o and directly use it without re-compiling. +Authors: - Author: Sten Wang, 886-3-5798797-8517, E-mail: sten_wang@davicom.com.tw +Sten Wang <sten_wang@davicom.com.tw > : Original Author +Tobias Ringstrom <tori@unhappy.mine.nu> : Current Maintainer + +Contributors: + +Marcelo Tosatti <marcelo@conectiva.com.br> +Alan Cox <alan@redhat.com> +Jeff Garzik <jgarzik@pobox.com> +Vojtech Pavlik <vojtech@suse.cz> diff --git a/Documentation/networking/fib_trie.txt b/Documentation/networking/fib_trie.txt new file mode 100644 index 000000000000..f50d0c673c57 --- /dev/null +++ b/Documentation/networking/fib_trie.txt @@ -0,0 +1,145 @@ + LC-trie implementation notes. + +Node types +---------- +leaf + An end node with data. This has a copy of the relevant key, along + with 'hlist' with routing table entries sorted by prefix length. + See struct leaf and struct leaf_info. + +trie node or tnode + An internal node, holding an array of child (leaf or tnode) pointers, + indexed through a subset of the key. See Level Compression. + +A few concepts explained +------------------------ +Bits (tnode) + The number of bits in the key segment used for indexing into the + child array - the "child index". See Level Compression. + +Pos (tnode) + The position (in the key) of the key segment used for indexing into + the child array. See Path Compression. + +Path Compression / skipped bits + Any given tnode is linked to from the child array of its parent, using + a segment of the key specified by the parent's "pos" and "bits" + In certain cases, this tnode's own "pos" will not be immediately + adjacent to the parent (pos+bits), but there will be some bits + in the key skipped over because they represent a single path with no + deviations. These "skipped bits" constitute Path Compression. + Note that the search algorithm will simply skip over these bits when + searching, making it necessary to save the keys in the leaves to + verify that they actually do match the key we are searching for. + +Level Compression / child arrays + the trie is kept level balanced moving, under certain conditions, the + children of a full child (see "full_children") up one level, so that + instead of a pure binary tree, each internal node ("tnode") may + contain an arbitrarily large array of links to several children. + Conversely, a tnode with a mostly empty child array (see empty_children) + may be "halved", having some of its children moved downwards one level, + in order to avoid ever-increasing child arrays. + +empty_children + the number of positions in the child array of a given tnode that are + NULL. + +full_children + the number of children of a given tnode that aren't path compressed. + (in other words, they aren't NULL or leaves and their "pos" is equal + to this tnode's "pos"+"bits"). + + (The word "full" here is used more in the sense of "complete" than + as the opposite of "empty", which might be a tad confusing.) + +Comments +--------- + +We have tried to keep the structure of the code as close to fib_hash as +possible to allow verification and help up reviewing. + +fib_find_node() + A good start for understanding this code. This function implements a + straightforward trie lookup. + +fib_insert_node() + Inserts a new leaf node in the trie. This is bit more complicated than + fib_find_node(). Inserting a new node means we might have to run the + level compression algorithm on part of the trie. + +trie_leaf_remove() + Looks up a key, deletes it and runs the level compression algorithm. + +trie_rebalance() + The key function for the dynamic trie after any change in the trie + it is run to optimize and reorganize. Tt will walk the trie upwards + towards the root from a given tnode, doing a resize() at each step + to implement level compression. + +resize() + Analyzes a tnode and optimizes the child array size by either inflating + or shrinking it repeatedly until it fullfills the criteria for optimal + level compression. This part follows the original paper pretty closely + and there may be some room for experimentation here. + +inflate() + Doubles the size of the child array within a tnode. Used by resize(). + +halve() + Halves the size of the child array within a tnode - the inverse of + inflate(). Used by resize(); + +fn_trie_insert(), fn_trie_delete(), fn_trie_select_default() + The route manipulation functions. Should conform pretty closely to the + corresponding functions in fib_hash. + +fn_trie_flush() + This walks the full trie (using nextleaf()) and searches for empty + leaves which have to be removed. + +fn_trie_dump() + Dumps the routing table ordered by prefix length. This is somewhat + slower than the corresponding fib_hash function, as we have to walk the + entire trie for each prefix length. In comparison, fib_hash is organized + as one "zone"/hash per prefix length. + +Locking +------- + +fib_lock is used for an RW-lock in the same way that this is done in fib_hash. +However, the functions are somewhat separated for other possible locking +scenarios. It might conceivably be possible to run trie_rebalance via RCU +to avoid read_lock in the fn_trie_lookup() function. + +Main lookup mechanism +--------------------- +fn_trie_lookup() is the main lookup function. + +The lookup is in its simplest form just like fib_find_node(). We descend the +trie, key segment by key segment, until we find a leaf. check_leaf() does +the fib_semantic_match in the leaf's sorted prefix hlist. + +If we find a match, we are done. + +If we don't find a match, we enter prefix matching mode. The prefix length, +starting out at the same as the key length, is reduced one step at a time, +and we backtrack upwards through the trie trying to find a longest matching +prefix. The goal is always to reach a leaf and get a positive result from the +fib_semantic_match mechanism. + +Inside each tnode, the search for longest matching prefix consists of searching +through the child array, chopping off (zeroing) the least significant "1" of +the child index until we find a match or the child index consists of nothing but +zeros. + +At this point we backtrack (t->stats.backtrack++) up the trie, continuing to +chop off part of the key in order to find the longest matching prefix. + +At this point we will repeatedly descend subtries to look for a match, and there +are some optimizations available that can provide us with "shortcuts" to avoid +descending into dead ends. Look for "HL_OPTIMIZE" sections in the code. + +To alleviate any doubts about the correctness of the route selection process, +a new netlink operation has been added. Look for NETLINK_FIB_LOOKUP, which +gives userland access to fib_lookup(). diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index a2c893a7475d..ab65714d95fc 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -304,57 +304,6 @@ tcp_low_latency - BOOLEAN changed would be a Beowulf compute cluster. Default: 0 -tcp_westwood - BOOLEAN - Enable TCP Westwood+ congestion control algorithm. - TCP Westwood+ is a sender-side only modification of the TCP Reno - protocol stack that optimizes the performance of TCP congestion - control. It is based on end-to-end bandwidth estimation to set - congestion window and slow start threshold after a congestion - episode. Using this estimation, TCP Westwood+ adaptively sets a - slow start threshold and a congestion window which takes into - account the bandwidth used at the time congestion is experienced. - TCP Westwood+ significantly increases fairness wrt TCP Reno in - wired networks and throughput over wireless links. - Default: 0 - -tcp_vegas_cong_avoid - BOOLEAN - Enable TCP Vegas congestion avoidance algorithm. - TCP Vegas is a sender-side only change to TCP that anticipates - the onset of congestion by estimating the bandwidth. TCP Vegas - adjusts the sending rate by modifying the congestion - window. TCP Vegas should provide less packet loss, but it is - not as aggressive as TCP Reno. - Default:0 - -tcp_bic - BOOLEAN - Enable BIC TCP congestion control algorithm. - BIC-TCP is a sender-side only change that ensures a linear RTT - fairness under large windows while offering both scalability and - bounded TCP-friendliness. The protocol combines two schemes - called additive increase and binary search increase. When the - congestion window is large, additive increase with a large - increment ensures linear RTT fairness as well as good - scalability. Under small congestion windows, binary search - increase provides TCP friendliness. - Default: 0 - -tcp_bic_low_window - INTEGER - Sets the threshold window (in packets) where BIC TCP starts to - adjust the congestion window. Below this threshold BIC TCP behaves - the same as the default TCP Reno. - Default: 14 - -tcp_bic_fast_convergence - BOOLEAN - Forces BIC TCP to more quickly respond to changes in congestion - window. Allows two flows sharing the same connection to converge - more rapidly. - Default: 1 - -tcp_default_win_scale - INTEGER - Sets the minimum window scale TCP will negotiate for on all - conections. - Default: 7 - tcp_tso_win_divisor - INTEGER This allows control over what percentage of the congestion window can be consumed by a single TSO frame. @@ -368,6 +317,11 @@ tcp_frto - BOOLEAN where packet loss is typically due to random radio interference rather than intermediate router congestion. +tcp_congestion_control - STRING + Set the congestion control algorithm to be used for new + connections. The algorithm "reno" is always available, but + additional choices may be available based on kernel configuration. + somaxconn - INTEGER Limit of socket listen() backlog, known in userspace as SOMAXCONN. Defaults to 128. See also tcp_max_syn_backlog for additional tuning diff --git a/Documentation/networking/phy.txt b/Documentation/networking/phy.txt new file mode 100644 index 000000000000..29ccae409031 --- /dev/null +++ b/Documentation/networking/phy.txt @@ -0,0 +1,288 @@ + +------- +PHY Abstraction Layer +(Updated 2005-07-21) + +Purpose + + Most network devices consist of set of registers which provide an interface + to a MAC layer, which communicates with the physical connection through a + PHY. The PHY concerns itself with negotiating link parameters with the link + partner on the other side of the network connection (typically, an ethernet + cable), and provides a register interface to allow drivers to determine what + settings were chosen, and to configure what settings are allowed. + + While these devices are distinct from the network devices, and conform to a + standard layout for the registers, it has been common practice to integrate + the PHY management code with the network driver. This has resulted in large + amounts of redundant code. Also, on embedded systems with multiple (and + sometimes quite different) ethernet controllers connected to the same + management bus, it is difficult to ensure safe use of the bus. + + Since the PHYs are devices, and the management busses through which they are + accessed are, in fact, busses, the PHY Abstraction Layer treats them as such. + In doing so, it has these goals: + + 1) Increase code-reuse + 2) Increase overall code-maintainability + 3) Speed development time for new network drivers, and for new systems + + Basically, this layer is meant to provide an interface to PHY devices which + allows network driver writers to write as little code as possible, while + still providing a full feature set. + +The MDIO bus + + Most network devices are connected to a PHY by means of a management bus. + Different devices use different busses (though some share common interfaces). + In order to take advantage of the PAL, each bus interface needs to be + registered as a distinct device. + + 1) read and write functions must be implemented. Their prototypes are: + + int write(struct mii_bus *bus, int mii_id, int regnum, u16 value); + int read(struct mii_bus *bus, int mii_id, int regnum); + + mii_id is the address on the bus for the PHY, and regnum is the register + number. These functions are guaranteed not to be called from interrupt + time, so it is safe for them to block, waiting for an interrupt to signal + the operation is complete + + 2) A reset function is necessary. This is used to return the bus to an + initialized state. + + 3) A probe function is needed. This function should set up anything the bus + driver needs, setup the mii_bus structure, and register with the PAL using + mdiobus_register. Similarly, there's a remove function to undo all of + that (use mdiobus_unregister). + + 4) Like any driver, the device_driver structure must be configured, and init + exit functions are used to register the driver. + + 5) The bus must also be declared somewhere as a device, and registered. + + As an example for how one driver implemented an mdio bus driver, see + drivers/net/gianfar_mii.c and arch/ppc/syslib/mpc85xx_devices.c + +Connecting to a PHY + + Sometime during startup, the network driver needs to establish a connection + between the PHY device, and the network device. At this time, the PHY's bus + and drivers need to all have been loaded, so it is ready for the connection. + At this point, there are several ways to connect to the PHY: + + 1) The PAL handles everything, and only calls the network driver when + the link state changes, so it can react. + + 2) The PAL handles everything except interrupts (usually because the + controller has the interrupt registers). + + 3) The PAL handles everything, but checks in with the driver every second, + allowing the network driver to react first to any changes before the PAL + does. + + 4) The PAL serves only as a library of functions, with the network device + manually calling functions to update status, and configure the PHY + + +Letting the PHY Abstraction Layer do Everything + + If you choose option 1 (The hope is that every driver can, but to still be + useful to drivers that can't), connecting to the PHY is simple: + + First, you need a function to react to changes in the link state. This + function follows this protocol: + + static void adjust_link(struct net_device *dev); + + Next, you need to know the device name of the PHY connected to this device. + The name will look something like, "phy0:0", where the first number is the + bus id, and the second is the PHY's address on that bus. + + Now, to connect, just call this function: + + phydev = phy_connect(dev, phy_name, &adjust_link, flags); + + phydev is a pointer to the phy_device structure which represents the PHY. If + phy_connect is successful, it will return the pointer. dev, here, is the + pointer to your net_device. Once done, this function will have started the + PHY's software state machine, and registered for the PHY's interrupt, if it + has one. The phydev structure will be populated with information about the + current state, though the PHY will not yet be truly operational at this + point. + + flags is a u32 which can optionally contain phy-specific flags. + This is useful if the system has put hardware restrictions on + the PHY/controller, of which the PHY needs to be aware. + + Now just make sure that phydev->supported and phydev->advertising have any + values pruned from them which don't make sense for your controller (a 10/100 + controller may be connected to a gigabit capable PHY, so you would need to + mask off SUPPORTED_1000baseT*). See include/linux/ethtool.h for definitions + for these bitfields. Note that you should not SET any bits, or the PHY may + get put into an unsupported state. + + Lastly, once the controller is ready to handle network traffic, you call + phy_start(phydev). This tells the PAL that you are ready, and configures the + PHY to connect to the network. If you want to handle your own interrupts, + just set phydev->irq to PHY_IGNORE_INTERRUPT before you call phy_start. + Similarly, if you don't want to use interrupts, set phydev->irq to PHY_POLL. + + When you want to disconnect from the network (even if just briefly), you call + phy_stop(phydev). + +Keeping Close Tabs on the PAL + + It is possible that the PAL's built-in state machine needs a little help to + keep your network device and the PHY properly in sync. If so, you can + register a helper function when connecting to the PHY, which will be called + every second before the state machine reacts to any changes. To do this, you + need to manually call phy_attach() and phy_prepare_link(), and then call + phy_start_machine() with the second argument set to point to your special + handler. + + Currently there are no examples of how to use this functionality, and testing + on it has been limited because the author does not have any drivers which use + it (they all use option 1). So Caveat Emptor. + +Doing it all yourself + + There's a remote chance that the PAL's built-in state machine cannot track + the complex interactions between the PHY and your network device. If this is + so, you can simply call phy_attach(), and not call phy_start_machine or + phy_prepare_link(). This will mean that phydev->state is entirely yours to + handle (phy_start and phy_stop toggle between some of the states, so you + might need to avoid them). + + An effort has been made to make sure that useful functionality can be + accessed without the state-machine running, and most of these functions are + descended from functions which did not interact with a complex state-machine. + However, again, no effort has been made so far to test running without the + state machine, so tryer beware. + + Here is a brief rundown of the functions: + + int phy_read(struct phy_device *phydev, u16 regnum); + int phy_write(struct phy_device *phydev, u16 regnum, u16 val); + + Simple read/write primitives. They invoke the bus's read/write function + pointers. + + void phy_print_status(struct phy_device *phydev); + + A convenience function to print out the PHY status neatly. + + int phy_clear_interrupt(struct phy_device *phydev); + int phy_config_interrupt(struct phy_device *phydev, u32 interrupts); + + Clear the PHY's interrupt, and configure which ones are allowed, + respectively. Currently only supports all on, or all off. + + int phy_enable_interrupts(struct phy_device *phydev); + int phy_disable_interrupts(struct phy_device *phydev); + + Functions which enable/disable PHY interrupts, clearing them + before and after, respectively. + + int phy_start_interrupts(struct phy_device *phydev); + int phy_stop_interrupts(struct phy_device *phydev); + + Requests the IRQ for the PHY interrupts, then enables them for + start, or disables then frees them for stop. + + struct phy_device * phy_attach(struct net_device *dev, const char *phy_id, + u32 flags); + + Attaches a network device to a particular PHY, binding the PHY to a generic + driver if none was found during bus initialization. Passes in + any phy-specific flags as needed. + + int phy_start_aneg(struct phy_device *phydev); + + Using variables inside the phydev structure, either configures advertising + and resets autonegotiation, or disables autonegotiation, and configures + forced settings. + + static inline int phy_read_status(struct phy_device *phydev); + + Fills the phydev structure with up-to-date information about the current + settings in the PHY. + + void phy_sanitize_settings(struct phy_device *phydev) + + Resolves differences between currently desired settings, and + supported settings for the given PHY device. Does not make + the changes in the hardware, though. + + int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd); + int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd); + + Ethtool convenience functions. + + int phy_mii_ioctl(struct phy_device *phydev, + struct mii_ioctl_data *mii_data, int cmd); + + The MII ioctl. Note that this function will completely screw up the state + machine if you write registers like BMCR, BMSR, ADVERTISE, etc. Best to + use this only to write registers which are not standard, and don't set off + a renegotiation. + + +PHY Device Drivers + + With the PHY Abstraction Layer, adding support for new PHYs is + quite easy. In some cases, no work is required at all! However, + many PHYs require a little hand-holding to get up-and-running. + +Generic PHY driver + + If the desired PHY doesn't have any errata, quirks, or special + features you want to support, then it may be best to not add + support, and let the PHY Abstraction Layer's Generic PHY Driver + do all of the work. + +Writing a PHY driver + + If you do need to write a PHY driver, the first thing to do is + make sure it can be matched with an appropriate PHY device. + This is done during bus initialization by reading the device's + UID (stored in registers 2 and 3), then comparing it to each + driver's phy_id field by ANDing it with each driver's + phy_id_mask field. Also, it needs a name. Here's an example: + + static struct phy_driver dm9161_driver = { + .phy_id = 0x0181b880, + .name = "Davicom DM9161E", + .phy_id_mask = 0x0ffffff0, + ... + } + + Next, you need to specify what features (speed, duplex, autoneg, + etc) your PHY device and driver support. Most PHYs support + PHY_BASIC_FEATURES, but you can look in include/mii.h for other + features. + + Each driver consists of a number of function pointers: + + config_init: configures PHY into a sane state after a reset. + For instance, a Davicom PHY requires descrambling disabled. + probe: Does any setup needed by the driver + suspend/resume: power management + config_aneg: Changes the speed/duplex/negotiation settings + read_status: Reads the current speed/duplex/negotiation settings + ack_interrupt: Clear a pending interrupt + config_intr: Enable or disable interrupts + remove: Does any driver take-down + + Of these, only config_aneg and read_status are required to be + assigned by the driver code. The rest are optional. Also, it is + preferred to use the generic phy driver's versions of these two + functions if at all possible: genphy_read_status and + genphy_config_aneg. If this is not possible, it is likely that + you only need to perform some actions before and after invoking + these functions, and so your functions will wrap the generic + ones. + + Feel free to look at the Marvell, Cicada, and Davicom drivers in + drivers/net/phy/ for examples (the lxt and qsemi drivers have + not been tested as of this writing) diff --git a/Documentation/networking/tcp.txt b/Documentation/networking/tcp.txt index 71749007091e..0fa300425575 100644 --- a/Documentation/networking/tcp.txt +++ b/Documentation/networking/tcp.txt @@ -1,5 +1,72 @@ -How the new TCP output machine [nyi] works. +TCP protocol +============ + +Last updated: 21 June 2005 + +Contents +======== + +- Congestion control +- How the new TCP output machine [nyi] works + +Congestion control +================== + +The following variables are used in the tcp_sock for congestion control: +snd_cwnd The size of the congestion window +snd_ssthresh Slow start threshold. We are in slow start if + snd_cwnd is less than this. +snd_cwnd_cnt A counter used to slow down the rate of increase + once we exceed slow start threshold. +snd_cwnd_clamp This is the maximum size that snd_cwnd can grow to. +snd_cwnd_stamp Timestamp for when congestion window last validated. +snd_cwnd_used Used as a highwater mark for how much of the + congestion window is in use. It is used to adjust + snd_cwnd down when the link is limited by the + application rather than the network. + +As of 2.6.13, Linux supports pluggable congestion control algorithms. +A congestion control mechanism can be registered through functions in +tcp_cong.c. The functions used by the congestion control mechanism are +registered via passing a tcp_congestion_ops struct to +tcp_register_congestion_control. As a minimum name, ssthresh, +cong_avoid, min_cwnd must be valid. +Private data for a congestion control mechanism is stored in tp->ca_priv. +tcp_ca(tp) returns a pointer to this space. This is preallocated space - it +is important to check the size of your private data will fit this space, or +alternatively space could be allocated elsewhere and a pointer to it could +be stored here. + +There are three kinds of congestion control algorithms currently: The +simplest ones are derived from TCP reno (highspeed, scalable) and just +provide an alternative the congestion window calculation. More complex +ones like BIC try to look at other events to provide better +heuristics. There are also round trip time based algorithms like +Vegas and Westwood+. + +Good TCP congestion control is a complex problem because the algorithm +needs to maintain fairness and performance. Please review current +research and RFC's before developing new modules. + +The method that is used to determine which congestion control mechanism is +determined by the setting of the sysctl net.ipv4.tcp_congestion_control. +The default congestion control will be the last one registered (LIFO); +so if you built everything as modules. the default will be reno. If you +build with the default's from Kconfig, then BIC will be builtin (not a module) +and it will end up the default. + +If you really want a particular default value then you will need +to set it with the sysctl. If you use a sysctl, the module will be autoloaded +if needed and you will get the expected protocol. If you ask for an +unknown congestion method, then the sysctl attempt will fail. + +If you remove a tcp congestion control module, then you will get the next +available one. Since reno can not be built as a module, and can not be +deleted, it will always be available. + +How the new TCP output machine [nyi] works. +=========================================== Data is kept on a single queue. The skb->users flag tells us if the frame is one that has been queued already. To add a frame we throw it on the end. Ack diff --git a/Documentation/networking/wanpipe.txt b/Documentation/networking/wanpipe.txt deleted file mode 100644 index aea20cd2a56e..000000000000 --- a/Documentation/networking/wanpipe.txt +++ /dev/null @@ -1,622 +0,0 @@ ------------------------------------------------------------------------------- -Linux WAN Router Utilities Package ------------------------------------------------------------------------------- -Version 2.2.1 -Mar 28, 2001 -Author: Nenad Corbic <ncorbic@sangoma.com> -Copyright (c) 1995-2001 Sangoma Technologies Inc. ------------------------------------------------------------------------------- - -INTRODUCTION - -Wide Area Networks (WANs) are used to interconnect Local Area Networks (LANs) -and/or stand-alone hosts over vast distances with data transfer rates -significantly higher than those achievable with commonly used dial-up -connections. - -Usually an external device called `WAN router' sitting on your local network -or connected to your machine's serial port provides physical connection to -WAN. Although router's job may be as simple as taking your local network -traffic, converting it to WAN format and piping it through the WAN link, these -devices are notoriously expensive, with prices as much as 2 - 5 times higher -then the price of a typical PC box. - -Alternatively, considering robustness and multitasking capabilities of Linux, -an internal router can be built (most routers use some sort of stripped down -Unix-like operating system anyway). With a number of relatively inexpensive WAN -interface cards available on the market, a perfectly usable router can be -built for less than half a price of an external router. Yet a Linux box -acting as a router can still be used for other purposes, such as fire-walling, -running FTP, WWW or DNS server, etc. - -This kernel module introduces the notion of a WAN Link Driver (WLD) to Linux -operating system and provides generic hardware-independent services for such -drivers. Why can existing Linux network device interface not be used for -this purpose? Well, it can. However, there are a few key differences between -a typical network interface (e.g. Ethernet) and a WAN link. - -Many WAN protocols, such as X.25 and frame relay, allow for multiple logical -connections (known as `virtual circuits' in X.25 terminology) over a single -physical link. Each such virtual circuit may (and almost always does) lead -to a different geographical location and, therefore, different network. As a -result, it is the virtual circuit, not the physical link, that represents a -route and, therefore, a network interface in Linux terms. - -To further complicate things, virtual circuits are usually volatile in nature -(excluding so called `permanent' virtual circuits or PVCs). With almost no -time required to set up and tear down a virtual circuit, it is highly desirable -to implement on-demand connections in order to minimize network charges. So -unlike a typical network driver, the WAN driver must be able to handle multiple -network interfaces and cope as multiple virtual circuits come into existence -and go away dynamically. - -Last, but not least, WAN configuration is much more complex than that of say -Ethernet and may well amount to several dozens of parameters. Some of them -are "link-wide" while others are virtual circuit-specific. The same holds -true for WAN statistics which is by far more extensive and extremely useful -when troubleshooting WAN connections. Extending the ifconfig utility to suit -these needs may be possible, but does not seem quite reasonable. Therefore, a -WAN configuration utility and corresponding application programmer's interface -is needed for this purpose. - -Most of these problems are taken care of by this module. Its goal is to -provide a user with more-or-less standard look and feel for all WAN devices and -assist a WAN device driver writer by providing common services, such as: - - o User-level interface via /proc file system - o Centralized configuration - o Device management (setup, shutdown, etc.) - o Network interface management (dynamic creation/destruction) - o Protocol encapsulation/decapsulation - -To ba able to use the Linux WAN Router you will also need a WAN Tools package -available from - - ftp.sangoma.com/pub/linux/current_wanpipe/wanpipe-X.Y.Z.tgz - -where vX.Y.Z represent the wanpipe version number. - -For technical questions and/or comments please e-mail to ncorbic@sangoma.com. -For general inquiries please contact Sangoma Technologies Inc. by - - Hotline: 1-800-388-2475 (USA and Canada, toll free) - Phone: (905) 474-1990 ext: 106 - Fax: (905) 474-9223 - E-mail: dm@sangoma.com (David Mandelstam) - WWW: http://www.sangoma.com - - -INSTALLATION - -Please read the WanpipeForLinux.pdf manual on how to -install the WANPIPE tools and drivers properly. - - -After installing wanpipe package: /usr/local/wanrouter/doc. -On the ftp.sangoma.com : /linux/current_wanpipe/doc - - -COPYRIGHT AND LICENSING INFORMATION - -This program is free software; you can redistribute it and/or modify it under -the terms of the GNU General Public License as published by the Free Software -Foundation; either version 2, or (at your option) any later version. - -This program is distributed in the hope that it will be useful, but WITHOUT -ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS -FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. - -You should have received a copy of the GNU General Public License along with -this program; if not, write to the Free Software Foundation, Inc., 675 Mass -Ave, Cambridge, MA 02139, USA. - - - -ACKNOWLEDGEMENTS - -This product is based on the WANPIPE(tm) Multiprotocol WAN Router developed -by Sangoma Technologies Inc. for Linux 2.0.x and 2.2.x. Success of the WANPIPE -together with the next major release of Linux kernel in summer 1996 commanded -adequate changes to the WANPIPE code to take full advantage of new Linux -features. - -Instead of continuing developing proprietary interface tied to Sangoma WAN -cards, we decided to separate all hardware-independent code into a separate -module and defined two levels of interfaces - one for user-level applications -and another for kernel-level WAN drivers. WANPIPE is now implemented as a -WAN driver compliant with the WAN Link Driver interface. Also a general -purpose WAN configuration utility and a set of shell scripts was developed to -support WAN router at the user level. - -Many useful ideas concerning hardware-independent interface implementation -were given by Mike McLagan <mike.mclagan@linux.org> and his implementation -of the Frame Relay router and drivers for Sangoma cards (dlci/sdla). - -With the new implementation of the APIs being incorporated into the WANPIPE, -a special thank goes to Alan Cox in providing insight into BSD sockets. - -Special thanks to all the WANPIPE users who performed field-testing, reported -bugs and made valuable comments and suggestions that help us to improve this -product. - - - -NEW IN THIS RELEASE - - o Updated the WANCFG utility - Calls the pppconfig to configure the PPPD - for async connections. - - o Added the PPPCONFIG utility - Used to configure the PPPD dameon for the - WANPIPE Async PPP and standard serial port. - The wancfg calls the pppconfig to configure - the pppd. - - o Fixed the PCI autodetect feature. - The SLOT 0 was used as an autodetect option - however, some high end PC's slot numbers start - from 0. - - o This release has been tested with the new backupd - daemon release. - - -PRODUCT COMPONENTS AND RELATED FILES - -/etc: (or user defined) - wanpipe1.conf default router configuration file - -/lib/modules/X.Y.Z/misc: - wanrouter.o router kernel loadable module - af_wanpipe.o wanpipe api socket module - -/lib/modules/X.Y.Z/net: - sdladrv.o Sangoma SDLA support module - wanpipe.o Sangoma WANPIPE(tm) driver module - -/proc/net/wanrouter - Config reads current router configuration - Status reads current router status - {name} reads WAN driver statistics - -/usr/sbin: - wanrouter wanrouter start-up script - wanconfig wanrouter configuration utility - sdladump WANPIPE adapter memory dump utility - fpipemon Monitor for Frame Relay - cpipemon Monitor for Cisco HDLC - ppipemon Monitor for PPP - xpipemon Monitor for X25 - wpkbdmon WANPIPE keyboard led monitor/debugger - -/usr/local/wanrouter: - README this file - COPYING GNU General Public License - Setup installation script - Filelist distribution definition file - wanrouter.rc meta-configuration file - (used by the Setup and wanrouter script) - -/usr/local/wanrouter/doc: - wanpipeForLinux.pdf WAN Router User's Manual - -/usr/local/wanrouter/patches: - wanrouter-v2213.gz patch for Linux kernels 2.2.11 up to 2.2.13. - wanrouter-v2214.gz patch for Linux kernel 2.2.14. - wanrouter-v2215.gz patch for Linux kernels 2.2.15 to 2.2.17. - wanrouter-v2218.gz patch for Linux kernels 2.2.18 and up. - wanrouter-v240.gz patch for Linux kernel 2.4.0. - wanrouter-v242.gz patch for Linux kernel 2.4.2 and up. - wanrouter-v2034.gz patch for Linux kernel 2.0.34 - wanrouter-v2036.gz patch for Linux kernel 2.0.36 and up. - -/usr/local/wanrouter/patches/kdrivers: - Sources of the latest WANPIPE device drivers. - These are used to UPGRADE the linux kernel to the newest - version if the kernel source has already been pathced with - WANPIPE drivers. - -/usr/local/wanrouter/samples: - interface sample interface configuration file - wanpipe1.cpri CHDLC primary port - wanpipe2.csec CHDLC secondary port - wanpipe1.fr Frame Relay protocol - wanpipe1.ppp PPP protocol ) - wanpipe1.asy CHDLC ASYNC protocol - wanpipe1.x25 X25 protocol - wanpipe1.stty Sync TTY driver (Used by Kernel PPPD daemon) - wanpipe1.atty Async TTY driver (Used by Kernel PPPD daemon) - wanrouter.rc sample meta-configuration file - -/usr/local/wanrouter/util: - * wan-tools utilities source code - -/usr/local/wanrouter/api/x25: - * x25 api sample programs. -/usr/local/wanrouter/api/chdlc: - * chdlc api sample programs. -/usr/local/wanrouter/api/fr: - * fr api sample programs. -/usr/local/wanrouter/config/wancfg: - wancfg WANPIPE GUI configuration program. - Creates wanpipe#.conf files. -/usr/local/wanrouter/config/cfgft1: - cfgft1 GUI CSU/DSU configuration program. - -/usr/include/linux: - wanrouter.h router API definitions - wanpipe.h WANPIPE API definitions - sdladrv.h SDLA support module API definitions - sdlasfm.h SDLA firmware module definitions - if_wanpipe.h WANPIPE Socket definitions - if_wanpipe_common.h WANPIPE Socket/Driver common definitions. - sdlapci.h WANPIPE PCI definitions - - -/usr/src/linux/net/wanrouter: - * wanrouter source code - -/var/log: - wanrouter wanrouter start-up log (created by the Setup script) - -/var/lock: (or /var/lock/subsys for RedHat) - wanrouter wanrouter lock file (created by the Setup script) - -/usr/local/wanrouter/firmware: - fr514.sfm Frame relay firmware for Sangoma S508/S514 card - cdual514.sfm Dual Port Cisco HDLC firmware for Sangoma S508/S514 card - ppp514.sfm PPP Firmware for Sangoma S508 and S514 cards - x25_508.sfm X25 Firmware for Sangoma S508 card. - - -REVISION HISTORY - -1.0.0 December 31, 1996 Initial version - -1.0.1 January 30, 1997 Status and statistics can be read via /proc - filesystem entries. - -1.0.2 April 30, 1997 Added UDP management via monitors. - -1.0.3 June 3, 1997 UDP management for multiple boards using Frame - Relay and PPP - Enabled continuous transmission of Configure - Request Packet for PPP (for 508 only) - Connection Timeout for PPP changed from 900 to 0 - Flow Control Problem fixed for Frame Relay - -1.0.4 July 10, 1997 S508/FT1 monitoring capability in fpipemon and - ppipemon utilities. - Configurable TTL for UDP packets. - Multicast and Broadcast IP source addresses are - silently discarded. - -1.0.5 July 28, 1997 Configurable T391,T392,N391,N392,N393 for Frame - Relay in router.conf. - Configurable Memory Address through router.conf - for Frame Relay, PPP and X.25. (commenting this - out enables auto-detection). - Fixed freeing up received buffers using kfree() - for Frame Relay and X.25. - Protect sdla_peek() by calling save_flags(), - cli() and restore_flags(). - Changed number of Trace elements from 32 to 20 - Added DLCI specific data monitoring in FPIPEMON. -2.0.0 Nov 07, 1997 Implemented protection of RACE conditions by - critical flags for FRAME RELAY and PPP. - DLCI List interrupt mode implemented. - IPX support in FRAME RELAY and PPP. - IPX Server Support (MARS) - More driver specific stats included in FPIPEMON - and PIPEMON. - -2.0.1 Nov 28, 1997 Bug Fixes for version 2.0.0. - Protection of "enable_irq()" while - "disable_irq()" has been enabled from any other - routine (for Frame Relay, PPP and X25). - Added additional Stats for Fpipemon and Ppipemon - Improved Load Sharing for multiple boards - -2.0.2 Dec 09, 1997 Support for PAP and CHAP for ppp has been - implemented. - -2.0.3 Aug 15, 1998 New release supporting Cisco HDLC, CIR for Frame - relay, Dynamic IP assignment for PPP and Inverse - Arp support for Frame-relay. Man Pages are - included for better support and a new utility - for configuring FT1 cards. - -2.0.4 Dec 09, 1998 Dual Port support for Cisco HDLC. - Support for HDLC (LAPB) API. - Supports BiSync Streaming code for S502E - and S503 cards. - Support for Streaming HDLC API. - Provides a BSD socket interface for - creating applications using BiSync - streaming. - -2.0.5 Aug 04, 1999 CHDLC initializatin bug fix. - PPP interrupt driven driver: - Fix to the PPP line hangup problem. - New PPP firmware - Added comments to the startup SYSTEM ERROR messages - Xpipemon debugging application for the X25 protocol - New USER_MANUAL.txt - Fixed the odd boundary 4byte writes to the board. - BiSync Streaming code has been taken out. - Available as a patch. - Streaming HDLC API has been taken out. - Available as a patch. - -2.0.6 Aug 17, 1999 Increased debugging in statup scripts - Fixed insallation bugs from 2.0.5 - Kernel patch works for both 2.2.10 and 2.2.11 kernels. - There is no functional difference between the two packages - -2.0.7 Aug 26, 1999 o Merged X25API code into WANPIPE. - o Fixed a memeory leak for X25API - o Updated the X25API code for 2.2.X kernels. - o Improved NEM handling. - -2.1.0 Oct 25, 1999 o New code for S514 PCI Card - o New CHDLC and Frame Relay drivers - o PPP and X25 are not supported in this release - -2.1.1 Nov 30, 1999 o PPP support for S514 PCI Cards - -2.1.3 Apr 06, 2000 o Socket based x25api - o Socket based chdlc api - o Socket based fr api - o Dual Port Receive only CHDLC support. - o Asynchronous CHDLC support (Secondary Port) - o cfgft1 GUI csu/dsu configurator - o wancfg GUI configuration file - configurator. - o Architectual directory changes. - -beta-2.1.4 Jul 2000 o Dynamic interface configuration: - Network interfaces reflect the state - of protocol layer. If the protocol becomes - disconnected, driver will bring down - the interface. Once the protocol reconnects - the interface will be brought up. - - Note: This option is turned off by default. - - o Dynamic wanrouter setup using 'wanconfig': - wanconfig utility can be used to - shutdown,restart,start or reconfigure - a virtual circuit dynamically. - - Frame Relay: Each DLCI can be: - created,stopped,restarted and reconfigured - dynamically using wanconfig. - - ex: wanconfig card wanpipe1 dev wp1_fr16 up - - o Wanrouter startup via command line arguments: - wanconfig also supports wanrouter startup via command line - arguments. Thus, there is no need to create a wanpipe#.conf - configuration file. - - o Socket based x25api update/bug fixes. - Added support for LCN numbers greater than 255. - Option to pass up modem messages. - Provided a PCI IRQ check, so a single S514 - card is guaranteed to have a non-sharing interrupt. - - o Fixes to the wancfg utility. - o New FT1 debugging support via *pipemon utilities. - o Frame Relay ARP support Enabled. - -beta3-2.1.4 Jul 2000 o X25 M_BIT Problem fix. - o Added the Multi-Port PPP - Updated utilites for the Multi-Port PPP. - -2.1.4 Aut 2000 - o In X25API: - Maximum packet an application can send - to the driver has been extended to 4096 bytes. - - Fixed the x25 startup bug. Enable - communications only after all interfaces - come up. HIGH SVC/PVC is used to calculate - the number of channels. - Enable protocol only after all interfaces - are enabled. - - o Added an extra state to the FT1 config, kernel module. - o Updated the pipemon debuggers. - - o Blocked the Multi-Port PPP from running on kernels - 2.2.16 or greater, due to syncppp kernel module - change. - -beta1-2.1.5 Nov 15 2000 - o Fixed the MulitPort PPP Support for kernels 2.2.16 and above. - 2.2.X kernels only - - o Secured the driver UDP debugging calls - - All illegal netowrk debugging calls are reported to - the log. - - Defined a set of allowed commands, all other denied. - - o Cpipemon - - Added set FT1 commands to the cpipemon. Thus CSU/DSU - configuraiton can be performed using cpipemon. - All systems that cannot run cfgft1 GUI utility should - use cpipemon to configure the on board CSU/DSU. - - - o Keyboard Led Monitor/Debugger - - A new utilty /usr/sbin/wpkbdmon uses keyboard leds - to convey operatinal statistic information of the - Sangoma WANPIPE cards. - NUM_LOCK = Line State (On=connected, Off=disconnected) - CAPS_LOCK = Tx data (On=transmitting, Off=no tx data) - SCROLL_LOCK = Rx data (On=receiving, Off=no rx data - - o Hardware probe on module load and dynamic device allocation - - During WANPIPE module load, all Sangoma cards are probed - and found information is printed in the /var/log/messages. - - If no cards are found, the module load fails. - - Appropriate number of devices are dynamically loaded - based on the number of Sangoma cards found. - - Note: The kernel configuraiton option - CONFIG_WANPIPE_CARDS has been taken out. - - o Fixed the Frame Relay and Chdlc network interfaces so they are - compatible with libpcap libraries. Meaning, tcpdump, snort, - ethereal, and all other packet sniffers and debuggers work on - all WANPIPE netowrk interfaces. - - Set the network interface encoding type to ARPHRD_PPP. - This tell the sniffers that data obtained from the - network interface is in pure IP format. - Fix for 2.2.X kernels only. - - o True interface encoding option for Frame Relay and CHDLC - - The above fix sets the network interface encoding - type to ARPHRD_PPP, however some customers use - the encoding interface type to determine the - protocol running. Therefore, the TURE ENCODING - option will set the interface type back to the - original value. - - NOTE: If this option is used with Frame Relay and CHDLC - libpcap library support will be broken. - i.e. tcpdump will not work. - Fix for 2.2.x Kernels only. - - o Ethernet Bridgind over Frame Relay - - The Frame Relay bridging has been developed by - Kristian Hoffmann and Mark Wells. - - The Linux kernel bridge is used to send ethernet - data over the frame relay links. - For 2.2.X Kernels only. - - o Added extensive 2.0.X support. Most new features of - 2.1.5 for protocols Frame Relay, PPP and CHDLC are - supported under 2.0.X kernels. - -beta1-2.2.0 Dec 30 2000 - o Updated drivers for 2.4.X kernels. - o Updated drivers for SMP support. - o X25API is now able to share PCI interrupts. - o Took out a general polling routine that was used - only by X25API. - o Added appropriate locks to the dynamic reconfiguration - code. - o Fixed a bug in the keyboard debug monitor. - -beta2-2.2.0 Jan 8 2001 - o Patches for 2.4.0 kernel - o Patches for 2.2.18 kernel - o Minor updates to PPP and CHLDC drivers. - Note: No functinal difference. - -beta3-2.2.9 Jan 10 2001 - o I missed the 2.2.18 kernel patches in beta2-2.2.0 - release. They are included in this release. - -Stable Release -2.2.0 Feb 01 2001 - o Bug fix in wancfg GUI configurator. - The edit function didn't work properly. - - -bata1-2.2.1 Feb 09 2001 - o WANPIPE TTY Driver emulation. - Two modes of operation Sync and Async. - Sync: Using the PPPD daemon, kernel SyncPPP layer - and the Wanpipe sync TTY driver: a PPP protocol - connection can be established via Sangoma adapter, over - a T1 leased line. - - The 2.4.0 kernel PPP layer supports MULTILINK - protocol, that can be used to bundle any number of Sangoma - adapters (T1 lines) into one, under a single IP address. - Thus, efficiently obtaining multiple T1 throughput. - - NOTE: The remote side must also implement MULTILINK PPP - protocol. - - Async:Using the PPPD daemon, kernel AsyncPPP layer - and the WANPIPE async TTY driver: a PPP protocol - connection can be established via Sangoma adapter and - a modem, over a telephone line. - - Thus, the WANPIPE async TTY driver simulates a serial - TTY driver that would normally be used to interface the - MODEM to the linux kernel. - - o WANPIPE PPP Backup Utility - This utility will monitor the state of the PPP T1 line. - In case of failure, a dial up connection will be established - via pppd daemon, ether via a serial tty driver (serial port), - or a WANPIPE async TTY driver (in case serial port is unavailable). - - Furthermore, while in dial up mode, the primary PPP T1 link - will be monitored for signs of life. - - If the PPP T1 link comes back to life, the dial up connection - will be shutdown and T1 line re-established. - - - o New Setup installation script. - Option to UPGRADE device drivers if the kernel source has - already been patched with WANPIPE. - - Option to COMPILE WANPIPE modules against the currently - running kernel, thus no need for manual kernel and module - re-compilatin. - - o Updates and Bug Fixes to wancfg utility. - -bata2-2.2.1 Feb 20 2001 - - o Bug fixes to the CHDLC device drivers. - The driver had compilation problems under kernels - 2.2.14 or lower. - - o Bug fixes to the Setup installation script. - The device drivers compilation options didn't work - properly. - - o Update to the wpbackupd daemon. - Optimized the cross-over times, between the primary - link and the backup dialup. - -beta3-2.2.1 Mar 02 2001 - o Patches for 2.4.2 kernel. - - o Bug fixes to util/ make files. - o Bug fixes to the Setup installation script. - - o Took out the backupd support and made it into - as separate package. - -beta4-2.2.1 Mar 12 2001 - - o Fix to the Frame Relay Device driver. - IPSAC sends a packet of zero length - header to the frame relay driver. The - driver tries to push its own 2 byte header - into the packet, which causes the driver to - crash. - - o Fix the WANPIPE re-configuration code. - Bug was found by trying to run the cfgft1 while the - interface was already running. - - o Updates to cfgft1. - Writes a wanpipe#.cfgft1 configuration file - once the CSU/DSU is configured. This file can - holds the current CSU/DSU configuration. - - - ->>>>>> END OF README <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< - - |