Fix BIRD VRF BGP router IDs

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: jbemmel

docs/caveats.md

@@ -87,7 +87,7 @@ nodes:
 * You must build the BIRD container image with the **netlab clab build bird** command. See [](build-bird) for build targets and version options.
 * BIRD is implemented as a pure control-plane daemon running as a container with a single external interface. You can set the node **role** to **router** to turn a BIRD instance into a more traditional networking device with a loopback interface.
 * _netlab_ installs BIRD software in a container image running Ubuntu 24.04 when you use the default **netlab clab build bird** target (~2.14). Other build targets install different BIRD releases — see [](build-bird).
-* BIRD supports a single router ID used for BGP and OSPF.
+* BIRD uses the node BGP router ID as the default router ID for BGP and OSPF protocol instances.
 * The VM or container running BIRD in host mode starts with static routes pointing to one of the adjacent routers (see [](linux-forwarding)). After establishing routing adjacencies, BIRD copies BGP and OSPF into the kernel IP routing table.
 
 ### OSPF Caveats

netsim/daemons/bird/bgp.j2

@@ -130,6 +130,9 @@ function {{ func_name }}( bool originate_default; bool rem_private_as ) {
 protocol bgp bgp_{{ ('vrf_' + vrf_name + '_') if vrf_name else '' }}{{ n.name }}_{{ af }} {
 {%     if vrf_name %}
   vrf "{{ vrf_name }}";
+{%       if 'router_id' in vrf_data.bgp %}
+  router id {{ vrf_data.bgp.router_id }};
+{%       endif %}
 {%     endif %}
 {%     set loopback = loopback|default({}) %}
 {%     set local = namespace(ip=loopback[af]|default('')) %}

netsim/validate/eos.py

@@ -46,8 +46,6 @@ def valid_ping(
     msg += f' size {pkt_len}'
 
   if expect == 'fail':
-    if not _result.stdout.strip():
-      return msg+' failed as expected'
     for kw in ("0 packets received","0 received","unreachable"):
       if kw in _result.stdout:
         return msg+' failed as expected'

netsim/validate/linux.py

@@ -68,8 +68,6 @@ def valid_ping(
     for kw in ("0 packets received","0 received","unreachable"):
       if kw in _result.stdout:
         return msg+' failed as expected'
-    if f"{ pkt_len + 8 if pkt_len else 64 } bytes from" not in _result.stdout:
-      return msg+' failed as expected'
     raise Exception(msg+' did not fail')
   else:
     if f"{ pkt_len + 8 if pkt_len else 64 } bytes from" in _result.stdout: