Page MenuHomeVyOS Platform

Config mismatch with FRR on misconfiguration of V6 peer
Closed, WontfixPublic

Description

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

Details

Difficulty level
Unknown (require assessment)
Version
VyOS 1.2.4
Why the issue appeared?
Will be filled on close
Is it a breaking change?
Unspecified (possibly destroys the router)
Issue type
Bug (incorrect behavior)

Event Timeline

bbabich created this object in space S1 VyOS Public.
syncer changed the task status from Open to Needs testing.Jan 6 2020, 12:40 AM
syncer assigned this task to Viacheslav.
syncer triaged this task as Normal priority.
syncer edited projects, added VyOS 1.3 Equuleus; removed VyOS 1.2 Crux (VyOS 1.2.5).
syncer added a subscriber: Viacheslav.
c-po subscribed.

This is fixed in 1.4 as proper input validation happens.

erkin set Issue type to Bug (incorrect behavior).Aug 31 2021, 5:56 PM