On Thu, Jan 30, 2025 at 03:01:14PM +0100, Claudio Jeker wrote:
> This diff fixes an issue with the default MP capability that is selected
> when no announce IPv4 / IPv6 capability is configured.
> 
> Until now a peer always had the unicast capability for the sessions
> address family enabled. So for example for an IPv4 session
> 	announce IPv4 unicast
> was automatically set.
> Now if you only want e.g. announce IPv4 vpn then you had to
> 	announce IPv4 none
> first to disable the default. This is awkward.

Yes.

> Here is a diff that only enables the unicast AFI when no other MP
> capability was set. Not sure if bgpd.conf.5 needs to be updated.
> It currently has:
>              The default is unicast for the same address family of the
>              session.
> Which is in my opinion OK.

Agreed.

> Now "announce IPv4 none" needed some extra handling so that it properly
> disables all IPv4 MP capabilities. Which results in an pure IPv4 session
> since there is no MP capability exchanged... but that's how BGP works.
> 
> This diff also changes new_peer() to only copy over the conf bits from the
> group peer. There is no need to copy over the full object.

Diff reads fine

ok tb