link fault reconfiguration

[pbarbieri1]

Hi, I have an ASR 1000x router that has to be connected with two fiber optic (ethernet link)  to two different brand router (not CISCO). My need is to configure or create a script that in case of one ethernet link go down all traffic will be moved on the second ethernet link. I want to avoid as possible , any involving of routing protocol as OSPF or other.. I can accept lost packets  in the time of reconfiguration, because the only traffic managed by router is multicast and this will be resend periodically without problem of losting packet. Can you support me ? i cant use multichassis LAG because cisco router will be connected with other two foreign routers that do not speak each other...

[Alex Pfeil · Accepted solution]

I think that using an SLA and tracking would be the best solution.  You can track whether an interface is up or not. However, only tracking if the interface is up is not the best practice.  You could have an instance where an interface remains up, but you cannot route through a device as well.  So, tracking just the interface would not cover all failover scenarios.  You can look into the Boolean or tracking.  Every scenario is different.  The best practice would be to determine the different types of failures that you want to account for, and create multiple tracking scenarios in order to fail to the second circuit.  We currently use IP SLA, tracking, and EEM scripting.

Please rate helpful posts.

[pbarbieri1]

Many thanks for your advices!

Thank you to you i have created two static routes to two different routers (2.2.2.2, 3.3.3.3)

R1(config)# ip route 0.0.0.0 0.0.0.0 2.2.2.2
R1(config)# ip route 0.0.0.0 0.0.0.0 3.3.3.3 10

(Administrative distance is 10 to consider this link as backup)

I have created a Probe IP SLA :

R1(config)# ip sla 1
R1(config)# icmp-echo 2.2.2.2 source-interface FastEthernet0/0
R1(config)# timeout 1000
R1(config)# threshold 1
R1(config)# frequency 1

R1(config)# ip sla schedule 1 life forever start-time now

I have created a Track object:

R1(config)# track 1 ip sla 1 reachability

and I have included in the static route the check:

R1(config)# ip route 0.0.0.0 0.0.0.0 2.2.2.2 track 1

R1(config)# ip route 0.0.0.0 0.0.0.0 3.3.3.3 20

 in case of first link is down , the router reconfigure on the second.

This should be run... I will test it now..thanks again