EEM usage for remote site?

John Blakley · ‎09-10-2009

All,

Is it possible to create an applet that would monitor a remote ip address and then perform an action based on that reachability?

What I have is something like this:

RTRA->RTRB->RTRC->RTRD

I want to be able to monitor RTRC's reachability to RTRD, but I need to do it from RTRB. You can't see it above, but RTRA also connects to RTRD. If RTRB can't get to RTRD through RTRC, I want RTRB to apply a policy map in the direction of RTRA because traffic will get redirected. Is this possible to do, or is there a better way of doing that?

Thanks,

John

HTH, John *** Please rate all useful posts ***

Collin Clark · ‎09-10-2009

John-

I think it's possible, but it would be pretty complex. I would post over in Network Management. Joe Clarke over there knows EEM like no other. Good luck and post the script when you get it working.

Joseph W. Doherty · ‎09-10-2009

"Is this possible to do, or is there a better way of doing that? "

I might be missing something here, but wouldn't a dynamic IGP deal with the situation you describe?

John Blakley · ‎09-10-2009

Well, yes and no. I'm using bgp between all of these sites, but the site between RTRA and RTRB is a 100mb connection that our SANS traffic goes over. If RTRA lost it's connection to RTRD (not shown, but exists in real world; it's a loop), then all branch traffic will get to RTRA via RTRC->RTRB->RTRA. When the link at either RTRA to RTRD or RTRC to RTRD goes down, I need to apply a policy map to RTRB to restrict traffic so the SANS doesn't take up all 100mb, which it takes up to 80-90mb now. So, the failover works good, but I'd like to apply the policy map automatically if the site went down at 2 in the morning.

Thanks,

John

HTH, John *** Please rate all useful posts ***

Joseph W. Doherty · ‎09-10-2009

From what you just described, perhaps QoS would be a better solution? It seems the real issue, in a failure situation, is SAN and other traffic sharing a link. For such, you could use QoS such that SAN has little, if almost any, adverse impact to the other traffic.

John Blakley · ‎09-10-2009

Joseph,

That's what I was planning on doing with the policy map. It looks like I may be able to monitor a remote router using snmp, but I'm still playing with that scenario.

Thanks,

John

HTH, John *** Please rate all useful posts ***

Joseph W. Doherty · ‎09-10-2009

What would you be unable to use the policy map all the time?