Single carrier multi-circuit asynchronous routing issue

Aaron Millisor aaron.millisor at bright.net
Tue Jan 20 12:21:32 CST 2009


Thank you both. Strict mode uRPF was indeed the problem. Took awhile for 
them to fix it for me, but at least it's fixed.

-- am

Anders Lindbäck wrote:
> On 7 jan 2009, at 21.05, Niels Bakker wrote:
> 
>> * aaron.millisor at bright.net (Aaron Millisor) [Wed 07 Jan 2009, 20:53 
>> CET]:
>> [..]
>>> If I were to prepend the network 1.1.1.0 to come in on 'sprint 1', 
>>> but have a route to 2.2.2.0 via 'sprint 2' so that traffic comes in 
>>> on one circuit but returns on the other, routing is broken. If I 
>>> change my route so that packets directed to 2.2.2.0 return on the 
>>> same circuit that the traffic is received on, everything works fine.
>>
>> You might be running into uRPF (unicast reverse path forward 
>> verification).
>>
>>
>>     -- Niels.
>>
> 
> Strict-mode uRPF will couse this, I am sure sprint support can help you 
> with it..
> 
> ------------------------------
> Anders Lindbäck
> anders.lindback at dnz.se
> 
> 





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