[c-nsp] OSPF per-prefix LFA

[Nick Hilliard]

This has nothing to do with OSPF virtual links.  I'm talking about the
virtual ethernet interfaces defined in your virtual lab.

You can test out whether it's doing what I suggested by changing the
hellotime value on the relevant interfaces.

Nick

On 28/05/2015 12:50, Mohammad Khalil wrote:
> Hi Nick and thanks for the reply
> All my routers are participating in area 0 , no virtual-link in place
> I shutdown the interface connected to R2 (from CSR or R1 side)
> 
> BR,
> Mohammad
> 
>> Date: Thu, 28 May 2015 12:36:50 +0100
>> From: nick at foobar.org
>> To: eng_mssk at hotmail.com; cisco-nsp at puck.nether.net
>> Subject: Re: [c-nsp] OSPF per-prefix LFA
>>
>> On 28/05/2015 12:24, Mohammad Khalil wrote:
>> > When I shutdown the interface with R2 (as I do not want to turn off the
>> > remote interface on R2 as I cannot turn on BFD on GNS3) and I have
>> > checked the route to 2.2.2.2 , it took about 5-6 seconds to install the
>> > same route via the backup path (via R3)
>>
>> did you try this by shutting down both sides of the virtual link at the
>> same time? The remote side will not detect carrier loss on a virtual link,
>> so ospf failover will be detected by according to the ospf deadtime.
>>
>> If you handle this with bfd, the failover time should be much faster. Last
>> time I measured this (me3600/100ms bfd), the failover time for l2vpn lsp
>> rerouting was reliably less than 400ms. I.e. the failover for regular ip
>> service should be a little less.
>>
>> Nick