When misconfiguring IPv6 BGP peer, a config mismatch between VyOS and FRR occurs, resulting in manual remediation to clear stale IPv6 neighbour from FRR via VTYSH to then re-configure successfully via VyOS.
+neighbor 2404:5C0:0:DC1::3 { + peer-group WWWires_9336 + update-source 2404:5C0:0:DC1::1/125 +} +neighbor 2404:5C0:0:DC2::3 { + peer-group WWWires_9336 + update-source 2404:5C0:0:DC2::1/125 +} [edit] bbabich@pauseq4rbdr1# commit [ protocols bgp 138466 ] % Invalid update-source, remove prefix length Error configuring routing subsystem. See log for more detailed information [edit] bbabich@pauseq4rbdr1# compare No changes between working and active configurations [edit] bbabich@pauseq4rbdr1# set protocols bgp 138466 neighbor 2404:5C0:0:DC2::3 update-source 2404:5C0:0:DC2::1 [edit] bbabich@pauseq4rbdr1# set protocols bgp 138466 neighbor 2404:5C0:0:DC1::3 update-source 2404:5C0:0:DC1::1 [edit] bbabich@pauseq4rbdr1# commit [ protocols bgp 138466 ] % Specify remote-as or peer-group commands first Error configuring routing subsystem. See log for more detailed information bbabich@pauseq4rbdr1# run show ipv6 bgp sum 2404:5c0:0:dc1::3 4 9336 52655 14 0 0 0 00:05:17 79318 ... bbabich@pauseq4rbdr1# del protocols bgp 138466 neighbor 2404:5C0:0:DC2::3 [edit] bbabich@pauseq4rbdr1# compare [edit protocols bgp 138466] -neighbor 2404:5C0:0:DC2::3 { - peer-group WWWires_9336 - update-source 2404:5C0:0:DC2::1 -} [edit] bbabich@pauseq4rbdr1# commit [ protocols bgp 138466 ] % Specify remote-as or peer-group commands first Error configuring routing subsystem. See log for more detailed information ... bbabich@pauseq4rbdr1# sudo vtysh Hello, this is FRRouting (version 7.2). Copyright 1996-2005 Kunihiro Ishiguro, et al. pauseq4rbdr1# configure term pauseq4rbdr1(config)# router bgp 138466 pauseq4rbdr1(config-router)# no neighbor 2404:5C0:0:DC2::3 pauseq4rbdr1(config-router)# exit pauseq4rbdr1(config)# exit pauseq4rbdr1# exit [edit] bbabich@pauseq4rbdr1# set protocols bgp 138466 neighbor 2404:5C0:0:DC2::3 peer-group WWWires_9336 [edit] bbabich@pauseq4rbdr1# set protocols bgp 138466 neighbor 2404:5C0:0:DC2::3 update-source 2404:5C0:0:DC2::1 [edit] bbabich@pauseq4rbdr1# commit [edit] bbabich@pauseq4rbdr1# save Saving configuration to '/config/config.boot'... Done ... bbabich@pauseq4rbdr1# run show ipv6 bgp sum 2404:5c0:0:dc1::3 4 9336 52810 15 0 0 0 00:06:38 79318 2404:5c0:0:dc2::3 4 9336 26079 3 0 0 0 00:00:13 79318