BGP - Want to receive own routes

Hi All,

Having a hard time deciphering this one.

Basically, on one peer im announcing out to upstreams 123.456.24.0/21 [made up for example sake], this is one of our ‘supernets’, and this is our primary, default site.

Recently we’ve split off 123.456.30.0/23, so the upper quarter of the /21 and announced it to a different upstream at a different site.

Our route filters basically track like this:

UPSTREAM-OUT
123.456.30.0/23 [23-24] reject
123.456.24.0/21 [21-24] accept

UPSTREAM-IN
123.456.30.0/23 [23-24] accept
123.456.24.0/21 [21-24] reject
0.0.0.0/0 [0-32] accept

So basically we do try and reject our own routes from being advertised back to us (just in case, as we push /24’s out via peering that our upstream is also on)

The problem I’m having is basically that upstream has the /23 route from our other site in their route table, trying to push it to us, but with those filters its still getting filtered out, and its really frustrating. Is there in-built ‘loop protection’ of some sort in Mikrotik where it would deny this route in because we are advertising out the /21 to this upstream provider?

Easy fix would be to static route out to upstream and that should fix it, but even with those filters saying to REJECT that route OUT - when I add the route it still advertises it to upstream so they then pick that up as the preferred route, and it gets stuck in a loop (argh).

Any help appreciated.

Thanks,
Joe

OK so this is 100% loop protection because its my own origin AS at the separate site.

Is there a way to have the filters allow own origin AS for a single prefix to bypass loop protection on this particular route?

Im such a wank. Allow-as-in is the obvious answer, I set it to 1 as it has 1 instance of my AS as the origin, all is swell.