Problem with OSPF NBMA and MikroTik

[Marek Wajdzik]

W dniu 2011-05-19 01:12, Ondrej Zajicek pisze:
> On Thu, May 19, 2011 at 12:36:38AM +0200, Adrian Czapek wrote:
>> W dniu 2011-05-19 00:41, Ondrej Zajicek pisze:
>>> On Wed, May 18, 2011 at 09:41:14PM +0200, Marek Wajdzik wrote:
>>>> Hi.
>>>>
>>>> 172.30.0.1 - compiled from fresh sources: bird 1.3.1 running debian
>>>> with kernel 2.6.38.6 x64
>>>> 172.30.0.120 - It is a mikrotik routeros version 5.2 node with configured ospf.
>>>>
>>>> When I restart the ospf in bird (birdc restrart OSPF) :P Mikrotik says:
>>> Hello
>>>
>>> Could you try BIRD with this (attached) patch?
>>>
>> Just applied this one and looks the issue is gone.
>> However, I had more ways to trigger 'wrong checksum' on MTs so I will
>> try them all now and report.
> Hello
>
> There is authentication data field in OSPF packet, which should be
> ignored if authentication is not used. Mikrotik OSPF, contrary to the
> RFC, checked the value of this field (or used the value when computed
> checksums) in that case. Because BIRD sent some random values in that,
> Mikrotik rejected that packets, that caused incompatibility.
> This patch fixed that.
>
> So the problem was triggered essentially by some unpredictable changes
> in memory and i would expect all the ways to trigger that problem
> caused that.
>
Hi. After 9 days of testing bird (ca. 90 routers, 700 pfx.) with this 
patch I didn't noticed any issues with ospf. It works really great now.
Thanks.