[FROG] ibgp regression on 8.5.2 ?

[Donatas Abraitis]

Hello, Mike!

With the 8.5.0 release, the new BGP attribute AIGP (Accumulated IGP Metric
Attribute) was introduced. This new attribute was mistakenly set as
Transitive. This was fixed (53afb27
<https://github.com/FRRouting/frr/commit/53afb27eb892a107c9426a01dbba82bee6fa86a7>)
with the 8.5.2 release, but it's not backward-compatible between 8.5.x
versions. We suggest using only the latest version of the 8.5 release.

If you see such errors/notifications, upgrade to the latest 8.5.x versions,
and avoid using 8.5.0, and 8.5.1.

AIGP attribute must be flagged as "Transitive"

%NOTIFICATION: received from neighbor X.Y.Z.W 3/4 (UPDATE Message
Error/Attribute
Flags Error) 14 bytes 80 1a 0b 01 00 0b 00 00 00 00 00 00 00 01

(This affects only iBGP sessions).

On Fri, Jun 30, 2023 at 12:09 AM mike tancsa <mike at sentex.net> wrote:

> Hi, I am guessing it is this commit ?
>
> commit 231e4de73f46b9c75a07bf0144aafce18aeb3a55
> Author: Donatas Abraitis <donatas at opensourcerouting.org>
> Date:   Mon May 8 22:49:10 2023 +0300
>
>      bgpd: Make sure AIGP attribute is non-transitive
>
>      The AIGP attribute is an optional, non-transitive BGP path attribute.
>
>      Signed-off-by: Donatas Abraitis <donatas at opensourcerouting.org>
>
>
> Is there a way to work around this in configs ?
>
>      ---Mike
>
> On 6/29/2023 2:39 PM, mike tancsa wrote:
> > I was updating an internal distribution router that got wedged in
> > vtysh from 8.5 to 8.5.2 and found all my ibgp peers would not come up.
> > Same error on the half dozen peers
> >
> > Jun 29 14:00:55 ibgp-4 bgpd[38150]: [HZN6M-XRM1G] %NOTIFICATION:
> > received from neighbor xx.yy.zz.251 3/4 (UPDATE Message
> > Error/Attribute Flags Error) 14 bytes 80 1a 0b 01 00 0b 00 00 00 00 00
> > 00 00 01
> > Jun 29 14:01:00 ibgp-4 bgpd[38150]: [HZN6M-XRM1G] %NOTIFICATION:
> > received from neighbor xx.yy.zz.251 3/4 (UPDATE Message
> > Error/Attribute Flags Error) 14 bytes 80 1a 0b 01 00 0b 00 00 00 00 00
> > 00 00 01
> > Jun 29 14:01:05 ibgp-4 bgpd[38150]: [HZN6M-XRM1G] %NOTIFICATION: sent
> > to neighbor xx.yy.zz.251 3/4 (UPDATE Message Error/Attribute Flags
> > Error) 14 bytes c0 1a 0b 01 0
> >
> > On the older versions of frr,
> >
> > [NYD0B-A3BTB][EC 33554433] AIGP attribute must be flagged as "Transitive"
> > [HZN6M-XRM1G] %NOTIFICATION: sent to neighbor xx.yy.zz.241 3/4 (UPDATE
> > Message Error/Attribute Flags Error) 14 bytes 80 1a 0b 01 0
> > [GW152-RVASS][EC 33554455] bgp_process_packet: BGP UPDATE receipt
> > failed for peer: xx.yy.zz.241
> >
> > I downgraded from 8.5.2 to 8.5.1 and all was good. Also, another peer
> > thats still running 7.x was fine with it all.
> >
> >
> > Nothing special about the config. One of the untouched boxes running 8.5
> >
> >  neighbor THOTLAN peer-group
> >  neighbor THOTLAN remote-as 11647
> >  neighbor THOTLAN description Core1LanEx
> >  neighbor THOTLAN update-source [dot.251]
> >  neighbor .241 peer-group HOTLAN
> >  neighbor .241 description The box the flipped out
> >  neighbor .241 bfd
> >   neighbor THOTLAN activate
> >   neighbor THOTLAN next-hop-self
> >   neighbor THOTLAN weight 111
> >
> > The box I tried to upgrade from 8.5 to 8.5.2 that then went back to 8.5.1
> >
> >  neighbor THOTLAN peer-group
> >  neighbor THOTLAN remote-as 11647
> >  neighbor THOTLAN update-source [dot.241]
> >  neighbor THOTLAN timers 16 50
> >  neighbor .251 description One of the many other peers that didnt like me
> >  neighbor .251 bfd
> >   neighbor THOTLAN activate
> >   neighbor THOTLAN next-hop-self
> >   neighbor THOTLAN soft-reconfiguration inbound
> >   neighbor THOTLAN weight 109
> >
> >
> >     ---Mike
> >
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.frrouting.org/pipermail/frog/attachments/20230630/4a6b4ef0/attachment-0001.htm>