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We have 3 sites over an MPLS. Each site has 2 x Cisco 2911's running HSRP. Each site has a tunnel interface from it's local site to the remote site over the MPLS. The tunnel interfaces are mirrored on each of the 2911 pairs where source IP is the local virtual IP and destination IP is the remote virtual IP. We are running OSPF across the network and all seems to be fine; the primary router has the tunnel interface up, the secondary router has the tunnel interface down (not admin down) and hence, neighbor relationships are correctly established. One of the sites has a 2911 and a 3725 in HSRP. From this site, we are having difficulty with OSPF whereby the neighbor site will build a relationship with the primary router, then go down, then build a relationship with the secondary router, then go down and etc; as a result, our logs are filled with neighbour adjacency alerts.

I should point out that the 3725 has FE ports and the 2911 has Gib ports; i've tried manually setting the tunnel interfaces with priorities but am still unable to make this work. I'm beginning to think we will need another 2911?

We are looking to have the capability whereby if the primary router goes down, the standby router kicks into gear, OSPF routes learned and business as usual.

Any ideas?

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    Out of interest, why is it configured this way? Why not have each of the routers run OSPF with the ISP's PE routers in the case of L3VPN, or with each other if you've got VPLS? HSRP is meant to be run on the LAN side as first hop redundancy, not the other way around
    – mellowd
    Jun 22, 2013 at 6:46
  • Did you try any debug in order to find the reason for the adjacency changes? Could you please add them to your question? Maybe also add the configuration of the pair of routers having issues?
    – Daniel Yuste Aroca
    Jun 22, 2013 at 8:42
  • what kind of tunnels? what kind of mpls services... mpls vpn? eompls? vpls? We need to see relevant configs and preferably a topology diagram.
    – Mike Pennington
    Jun 22, 2013 at 11:28
  • Please don't forget to accept whatever answer is useful to you
    – Mike Pennington
    Oct 7, 2013 at 12:52
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can post and accept your own answer.
    – Ron Maupin ♦
    Jan 5, 2021 at 2:37

2 Answers 2

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I would HIGHLY recommend getting rid of HSRP and using routing over the tunnels (both up all the time), whether OSPF or EIGRP. Set an inferior metric on one of the tunnels at both ends. Problem solved.

HSRP is BAD NEWS over WAN. I am struggling to see what use the HSRP is. As you're now seeing it also causes a lot of issues when overlaid on top of routing.

There is a reason they're called First Hop Redundancy Protocols in the textbook, their place is to provide redundancy for LAN client's default gateways i.e. the first hop.

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Are you sure you are not injecting the subnet with HSRP into OSPF (recursive routing). I use HSRP for SSLVPN and it works fine. that things work until you have an OSPF routing table is what suggests the recursive routing scenario to me. Another question is are you seeing in your logs HSRP primary moving around, which would suggest a problem at the head end.

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  • Thanks guys - I believe the issue is between the 3700 and 2911 as I have this working at 2 other sites without an issue. I've turned off HSRP at this particular site.
    – ik_tech
    Oct 7, 2013 at 22:19

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