topic Re: Advanced-routing ignores BGP local-pref in General Topics

Advanced-routing ignores BGP local-pref

dmgeurts — Fri, 28 Feb 2025 14:41:24 GMT

Troubleshooting a routing issue I've just discovered that the local preference isn't used for forwarding decisions when ECMP is enabled. Has anyone seen this before? I'm about to log a support case, but I thought I'd ask here in tandem.

What I see is that the inbound route map sets the local-preference, and ECMP then ignores this and uses all received prefixes as if they're equal. The peers are internal ebgp peers. I would have expected ECMP to consider the local preference set by the route map.

`show advanced-routing bgp filters route-map logical-router default ipv4 name <ROUTE-MAP>` shows the set local preference for each processed prefix.

`show advanced-routing bgp loc-rib-detail prefix <CIDR>` shows the received community, but the local preference is 0.

`show advanced-routing bgp route logical-router default afi ipv4` shows the BGP table, also with a local preference of 0.

Re: Advanced-grouting BGP local-pref of 0?!

dmgeurts — Fri, 28 Feb 2025 13:45:28 GMT

I've verified that as-path prepending on the (remote) bgp peer works as expected for what I'm trying to do. I'll update here if support comes back with something useful.

Platform is a PA-3410 running 11.1.4(h9)

Re: Advanced-routing ignores BGP local-pref

dmgeurts — Fri, 07 Mar 2025 19:22:15 GMT

If anyone else comes across the same behaviour, make sure to turn off graceful shutdown under logical router >> BGP >> General >> Options

Re: Advanced-routing ignores BGP local-pref

david_i — Tue, 19 Aug 2025 18:24:36 GMT

I don't even want to know how many hours of pain you just saved me. I just noticed this behavior a few days before implementation. Thank you!