One router, dual circuits, and passive interfaces

[CORY HEBERT]

Here's my scenario.  One router with dual circuits...both are active with OSPF routing across.  What I want to happen is, when a circuit starts taking more than 1000 errors in a minute...make that interface passive.  But once that happens...I don't want to shoot myself in the foot if the other circuit starts taking errors.  I don't want the other circuit to go passive and effectively bring down the site.

I currently have two independent scripts...one for circuit1, one for circuit2.  I thought about this solution: if one script is invoked, within THAT script, automatically remove the OTHER script so there's no chance it can run and shutdown the site...but that's not really a clean solution, and would require me to come back later to manually restore the removed script.

Any other ideas to accomplish this requirement?  Thank you.

[Joe Clarke]

What would be interesting to do is use a tracked object to store the current state.  Create a stub tracked object, then set it in your first script and check it in your second script.

track 1 stub-object

 default-state up

To set:

track set 1 state down

To read:

track read 1

if $_track_state eq down

 ! Exit here

end

[CORY HEBERT]

Thanks, Joseph!  Your response really got my gears turning, and I was able to get it working perfectly.  Here's what it ended up looking like:

track 1 stub-object
!
track 2 stub-object
!

event manager applet CIRUIT1_OSPF_DOWN
 event syslog pattern "%OSPF-5-ADJCHG.*Serial0/1/0.*to DOWN"
 action 10 track set 1 state down
event manager applet CIRUIT1_OSPF_UP
 event syslog pattern "%OSPF-5-ADJCHG.*Serial0/1/0.*to FULL"
 action 10 track set 1 state up
event manager applet CIRUIT2_OSPF_DOWN
 event syslog pattern "%OSPF-5-ADJCHG.*Serial0/0/0.*to DOWN"
 action 10 track set 2 state down
event manager applet CIRUIT2_OSPF_UP
 event syslog pattern "%OSPF-5-ADJCHG.*Serial0/0/0.*to FULL"
 action 10 track set 2 state up

!
event manager applet DIRTY_CIRCUIT1
 event interface name Serial0/1/0 parameter input_errors entry-op ge entry-val 100 entry-type increment poll-interval 60
 action 06   track read 2
 action 08   if $_track_state eq up
 action 10    if $_interface_delta_value ge 1000
 action 20     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute (MAKING INTERFACE PASSIVE)"
 action 20.1   cli command "enable"
 action 20.2   cli command "config t"
 action 20.3   cli command "router ospf 1"
 action 20.4   cli command "passive-interface Serial0/1/0"
 action 20.5   cli command "end"
 action 30    else
 action 40     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute"
 action 50    end
 action 60   elseif $_track_state eq down
 action 70    if $_interface_delta_value ge 1000
 action 80     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute (CANT MAKE INTERFACE PASSIVE SINCE OTHER CIRCUIT ALREADY PASSIVE)"
 action 90    else
 action 92     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute"
 action 94    end
 action 96   end

!
event manager applet DIRTY_CIRCUIT2
 event interface name Serial0/0/0 parameter input_errors entry-op ge entry-val 100 entry-type increment poll-interval 60
 action 06   track read 1
 action 08   if $_track_state eq up
 action 10    if $_interface_delta_value ge 1000
 action 20     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute (MAKING INTERFACE PASSIVE)"
 action 20.1   cli command "enable"
 action 20.2   cli command "config t"
 action 20.3   cli command "router ospf 1"
 action 20.4   cli command "passive-interface Serial0/0/0"
 action 20.5   cli command "end"
 action 30    else
 action 40     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute"
 action 50    end
 action 60   elseif $_track_state eq down
 action 70    if $_interface_delta_value ge 1000
 action 80     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute (CANT MAKE INTERFACE PASSIVE SINCE OTHER CIRCUIT ALREADY PASSIVE)"
 action 90    else
 action 92     syslog msg "$_interface_delta_value $_interface_parameter on $_interface_name in the past minute"
 action 94    end
 action 96   end
!