[c-nsp] Source address on BGP peering set up

[Piltrafilla]

Hi people,

Anyone knows how BGP on a Cisco router choose source IP address for
peering establishment if no "update-source" command is applied to
neighbor? Is it only the primary IP address on the closest interface
to neighbor?

For instance, let's say that you would like to set up a peering using
a secondary IP address to between two directly-connected neighbors. Is
it setting up loopbacks, static /32 routes and update-source on the
neighbors' config the only way to do it?

On bgpd of OpenBSD you could set up a "local-address" parameter per
neighbor or group that sets up source IP address used for that
peering. I haven't found any similar parameter on cisco bgp neighbors'
config.

Thanks in advance,

-- Piltrafilla