SNMP + Null Routes

Unanswered Question
Dec 16th, 2007
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Platform: Cisco 6500, and Cisco 3550

1)I want to read via SNMP, all routes that have been nulled.

2)I want to be able to put in new null routes.

3) I want to be able to remove null routes.

ie: read and write: ip route Null0 314324

I've looked and looked but could not find an OID that even came close to this, or any information online how how to add a null route via snmp or add a static route via snmp.

I need this information so I can automate some null routes that our system need to implement from time to time, and remove them as well.

Thank you for your help.


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Overall Rating: 5 (1 ratings)
Joe Clarke Sun, 12/16/2007 - 21:57
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Reading routes is doable using the ipRouteTable objects. For example, this CLI:

ip route Null0

Would look like the following in the ipRouteTable:

RFC1213-MIB::ipRouteDest. = IpAddress:

RFC1213-MIB::ipRouteIfIndex. = INTEGER: 27

RFC1213-MIB::ipRouteMetric1. = INTEGER: 0

RFC1213-MIB::ipRouteMetric2. = INTEGER: -1

RFC1213-MIB::ipRouteMetric3. = INTEGER: -1

RFC1213-MIB::ipRouteMetric4. = INTEGER: -1

RFC1213-MIB::ipRouteNextHop. = IpAddress:

RFC1213-MIB::ipRouteType. = INTEGER: direct(3)

RFC1213-MIB::ipRouteProto. = INTEGER: local(2)

RFC1213-MIB::ipRouteAge. = INTEGER: 0

RFC1213-MIB::ipRouteMask. = IpAddress:

RFC1213-MIB::ipRouteMetric5. = INTEGER: -1

RFC1213-MIB::ipRouteInfo. = OID: SNMPv2-SMI::zeroDotZero

In this example, ifIndex 27 is Null0.

While these objects are read-write, you will not be able to create new routing table entries via SNMP (only modify existing entries).

Creating routes is supported in the new IP-FORWARD-MIB (using the ipCidrRouteTable), but this table is not supported on the 3550, and I do not know what code your 6500 is running.


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