[c-nsp] PBR / EEM / OSPF SNMP MIB

[Adam Greene]

Hi,

 

Somewhat complicated conditional routing question to run by you all .

 

This is on a 3750 switch, 12.2(25)SEE2.

 

We want to route traffic sourced from a particular IP range out a particular
interface. This is simple to do using Policy Based Routing.

 

However, we want that route to be conditional upon the existence of a
particular route in the OSPF RIB, in this case an external type 2 default
route with a metric of 100. 

 

I understand that PBR only supports matches on source IP and packet length.
On the 3750, it also does not support object tracking.

 

This article suggests we could use EEM to track SNMP MIB objects and remove
the PBR depending on the value returned by an SNMP poll:
https://supportforums.cisco.com/document/31461/policy-based-routing-pbr-trac
king-catalyst-3xxx-switches-workaround-using-eem. 

 

So the question is . can SNMP be used to track whether an external type 2
default route with a metric of 100 is present in the OSPF RIB?

 

Thanks,

Adam