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

Script:
    Ping A Host

Script-Description:
    Ping a host and fire an issue if it's not reachable

Script-Filter:
    $IPAddress eq 10.30.3.1

Script-Devices:
    10.30.3.1

Script-Schedule:
    */3 * * * *
   

#################################################################
Action:
    Perform Ping

Action-Description:
    Run the ping command against our host

Action-Variables:
    SET: $hostDead = "no"

Action-Commands:
    ping 172.23.1.1

Output-Triggers:
    Parse Output

#################################################################
Trigger:
    Parse Output

Trigger-Description:
    Find out if we can ping our host, update a variable.

Trigger-Variables:
    $pingable string

Trigger-Template:
    Success rate is [[$pingable]] percent .+

Trigger-Commands:{ $pingable eq "0" }
    SET: $hostDead = "yes"

Output-Triggers:
    Run Command

##################################################################

Trigger:
    Run Command

Trigger-Description:
    Clear IP OSPF Proccess on 3750

Trigger-Filter:
    $hostDead eq "yes"

Trigger-Commands:
    clear ip ospf process \cmy
    copy run start \cm
    q

Output-Triggers:
     Host Down



#################################################################
Issue:
    Host Down

Issue-ID:
    pittsFWdown

Issue-Severity:
    error

Issue-Description:
    Cannot ping the remote host

Issue-Filter:
    $hostDead eq "yes"

Issue-Details:
    Host        $IPAddress
   
#################################################################

Here is the issue we created for this:

 Here is what the Script Script Schedule look slike for this: