PFsense > Cisco OSPF flapping

  • Hi all,

    I configured OSPF between my pfsense and cisco switch using broadcast, area 0 local subnets.

    However, on the Cisco I switched on debug and noticed OSPF constantly loading every 20 seconds to minute, debug also shows hello messages coming and going.

    I saw messages on the cisco along the lines of "Cannot see self in hello from pfsense IP". Has anyone faced this issue before?

    Cisco global mtu is 1500 and the Pfsense interface is the same.

    Happy for any input on this as it is driving me mad!


  • Ok I think I have resolved this, after going through debugs and more logs I saw the inactivity timer was being triggered on PFsense. This to me said it was not getting hello's from the multicast / neighbor.. therefore I created a firewall rule to allow any from the source of the neighbor to pfsense and the recurring adj messages stopped.

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