[Bird2] Doubt about Route Server function and iBGP

[Ondrej Zajicek]

On Mon, Sep 24, 2018 at 02:21:42PM -0300, heisenbug at xpto wrote:
> Hello Guys,
> 
> On bird1.6, I have deployed our Route Servers using the below
> architecture to split the load from the control plane:
> 
> Customer1 <-> RS1[pid0] <-> iBGP <-> RS2[pid1] <-> Customer2
> 
> And is working fine as RS until now [not inserting local AS on AS-PATH
> and not changing NH]. I'm planing to migrate to Bird2.0.2 with some new
> features, but when I do the same on Bird2.0.2, I have the AS from iBGP
> inserted on AS-PATH, just to let me know, this is an expected behavior
> on Bird2? I have tested in a lot of ways, but still the same results.

Hi

You are right, BIRD 2 would not insert local AS only if propagated from
EBGP-RS to EBGP-RS. The main motivation for the change is to better
handle the case when a route is propagated from EBGP to EBGP-RS, where it
makes sense to prepend local AS. You are right that in your case the old
behavior makes more sense.

-- 
Elen sila lumenn' omentielvo

Ondrej 'Santiago' Zajicek (email: santiago at crfreenet.org)
OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net)
"To err is human -- to blame it on a computer is even more so."