This directive enables RFC 1413-compliant logging of the remote user name for each connection, where the client machine runs identd or something similar. This information is logged in the access log using the %...l format string.

Note that this can cause serious latency problems accessing your server since every request requires one of these lookups to be performed. When firewalls or proxy servers are involved, each lookup might possibly fail and add a latency duration as defined by the IdentityCheckTimeout directive to each hit. So in general this is not very useful on public servers accessible from the Internet.

This directive specifies the timeout duration of an ident request. The default value of 30 seconds is recommended by RFC 1413, mainly because of possible network latency. However, you may want to adjust the timeout value according to your local network speed.