We have 2 VPN Tunnels connecting our Annapolis and Pittsburgh
offices. We found a bug in the Juniper Netscreen routers we are using
that causes routes to be dropped on the Pittsburgh Netscreen pointing
back to subnets in the Annapolis Office. Turns out the routes are all
routes sitting behind our Cisco Core Switch/Router.
We
initially wrote a CCS Script to tell us when the routes were down by
running a Ping from our Core Cisco router to a router in PIttsburgh.
This was great and notified us when the bug reared its nasty head.
However we did not know how to resolve other than rebooting the
NetScreen firewall.
Eventually we found a better way to get
the routes back by forcing the Cisco 3750 to restart OSPF by issuing
the command “clear ip ospf process \cmy”
So here is the
script that we wrote to run a ping from our Cisco 3750 to a Netscreen
across the VPN which checks if the Netscreen has a route back the Cisco
3750. If the ping fails we then raise an issue and run the “clear ip
ospf process \cmy” command to restart OSPF and get the routes back.
[ Click Here for Script ]