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| author | Anuradha Karuppiah <anuradhak@cumulusnetworks.com> | 2020-05-09 01:35:09 +0200 |
|---|---|---|
| committer | Anuradha Karuppiah <anuradhak@cumulusnetworks.com> | 2020-10-26 18:26:21 +0100 |
| commit | 74e2bd891d85d68250ce368cb538fb5404867238 (patch) | |
| tree | c8c58d5103b2227432f4a49d412fdef730178612 /bgpd/bgp_evpn_private.h | |
| parent | Merge pull request #7388 from donaldsharp/more_string (diff) | |
| download | frr-74e2bd891d85d68250ce368cb538fb5404867238.tar.xz frr-74e2bd891d85d68250ce368cb538fb5404867238.zip | |
bgpd: support for DF election in EVPN-MH
DF (Designated forwarder) election is used for picking a single
BUM-traffic forwarded per-ES. RFC7432 specifies a mechanism called
service carving for DF election. However that mechanism has many
disadvantages -
1. LBs poorly.
2. Doesn't allow for a controlled failover needed in upgrade
scenarios.
3. Not easy to hw accelerate.
To fix the poor performance of service carving alternate DF mechanisms
have been proposed via the following drafts -
draft-ietf-bess-evpn-df-election-framework
draft-ietf-bess-evpn-pref-df
This commit adds support for the pref-df election mechanism which
is used as the default. Other mechanisms including service-carving
may be added later.
In this mechanism one switch on an ES is elected as DF based on the
preference value; higher preference wins with IP address acting
as the tie-breaker (lower-IP wins if pref value is the same).
Sample output
=============
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
torm-11# sh bgp l2vpn evpn es 03:00:00:00:00:01:11:00:00:01
ESI: 03:00:00:00:00:01:11:00:00:01
Type: LR
RD: 27.0.0.15:6
Originator-IP: 27.0.0.15
Local ES DF preference: 100
VNI Count: 10
Remote VNI Count: 10
Inconsistent VNI VTEP Count: 0
Inconsistencies: -
VTEPs:
27.0.0.16 flags: EA df_alg: preference df_pref: 32767
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
torm-11# sh bgp l2vpn evpn route esi 03:00:00:00:00:01:11:00:00:01
*> [4]:[03:00:00:00:00:01:11:00:00:01]:[32]:[27.0.0.15]
27.0.0.15 32768 i
ET:8 ES-Import-Rt:00:00:00:00:01:11 DF: (alg: 2, pref: 100)
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Diffstat (limited to 'bgpd/bgp_evpn_private.h')
| -rw-r--r-- | bgpd/bgp_evpn_private.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/bgpd/bgp_evpn_private.h b/bgpd/bgp_evpn_private.h index 611566201..c47576c00 100644 --- a/bgpd/bgp_evpn_private.h +++ b/bgpd/bgp_evpn_private.h @@ -308,6 +308,17 @@ static inline void encode_es_rt_extcomm(struct ecommunity_val *eval, memcpy(&eval->val[2], mac, ETH_ALEN); } +static inline void encode_df_elect_extcomm(struct ecommunity_val *eval, + uint16_t pref) +{ + memset(eval, 0, sizeof(*eval)); + eval->val[0] = ECOMMUNITY_ENCODE_EVPN; + eval->val[1] = ECOMMUNITY_EVPN_SUBTYPE_DF_ELECTION; + eval->val[2] = EVPN_MH_DF_ALG_PREF; + eval->val[6] = (pref >> 8) & 0xff; + eval->val[7] = pref & 0xff; +} + static inline void encode_esi_label_extcomm(struct ecommunity_val *eval, bool single_active) { |