[c-nsp] Monitoring Routing Table

[Justin M. Streiner]

On Sat, 1 Nov 2008, Asad Hasan wrote:

> Is there an OID that can pull back number of routes within the routing
> table? OID which can generate results such as 'show ip ro summ'. I found OID
> 1.3.6.1.2.1.4.21.1.1 and 1.3.6.1.2.1.4.21.1.9 (IpRouteTable and
> IpRouteProto), but this pulls back every routing entry. Also is there an OID
> that can pull back similar information for a VRF.

Not sure about VRFs, as I don't use them at the moment, but you can run a 
count on the number of entries that are returned by polling ipRouteTable 
to get the number of routes.  You can also try it with ipRouteProto and 
just looking at connected + static + OSPF.  That might actually be better, 
if you carry IBGP w/full views on your routers since it will be less 
taxing on the router's CPU.  If you're planning to do this with something 
like MRTG, I believe it has an option you can to use to count the number 
of routes.  If you're not using MRTG, it would be easy enough to write a 
script to poll the appropriate OID and pipe the output into a counter to 
get the number you're looking for.

jms