how to manipulate OSPF routes using 2 links

[carl_townshend]

hi everybody

I have a question

I have a site whereby I have 2 wan links, back to a datacentre

I want certain traffic to go over 1 link and certain traffic over the other link.

How can I make 1 route to be prefererred to the other just for certain routes ?

cheers

Carl

[carl_townshend]

Hi There

to add, what is it best to track, should I track the physical interface of the other side ?

[Bilal Nawaz]

Hello, the ip sla icmp probe should be configured as close to the destination next hop as possible - just in the case it doesn't follow the policy based routing. After all, you could source from the LAN but you still might be able to get there, it will just be from a different path. In this case you want to make sure that the source is the interface closest to the next hop.

In my example you can see that i've used fa0/0 and fa0/1 which is closest to DC.

Hope this helps.

Please rate useful posts and remember to mark any solved questions as answered. Thank you.

[carl_townshend]

OK

A further question, how about traffic going back the other way from the DC to SITE A, wont we need to do the same that end so we dont get asymmetric routing ?

[Bilal Nawaz]

Yes - you will need it at both ends to control to and from type traffic.

If either links were down, they would failover with tracking in place.

Hope this helps

Sent from Cisco Technical Support iPhone App

[carl_townshend]

so lastly, you sould track the IP on the other end of the wan link with the source being the local wan link ?

[Bilal Nawaz]

Yes, because this is the paths that the traffic will take

Sounds like we're almost there! ;-)

Sent from Cisco Technical Support iPhone App

[carl_townshend]

Hi there

what are the recommened settings for the SLA probe timers ?

[Bilal Nawaz]

There are no recommended settings - It all depends on how quick you want to failover to the other method.

So you can tweak this setting.

Hope this helps

Please rate useful posts and remember to mark any solved questions as answered. Thank you.