SNMP Auto Discovery across multiple switches

[drumrb0y]

I've encountered two scenarios where SNMP auto-discovery fails to detect a device because it is more than one switch removed from the discovering entity:

1. - CiscoWorks fails to discover an AS5350 VPN gateway because it connects to the core network via a 3550 switch (which is turn connected to a 3500 switch);

2. - A Microsoft SMS server cannot discover the network because it connects to the network via a 3500 switch, which is in turn connected to another 3500 (with the ports in trunking mode) in the comm closet;

Am I correct in assertaining that SNMP will not allow auto-discovery across more than one switch, and that replacing the intervening switch with a router will alleviate the problem?

[amritpatek]

You can sniff and caputure the packets to diagonise, where exactly the problem occurs. This could be due to not getting added to database. Stop and Start the Database service, this should solve the problem.

[netnut]

Ciscoworks will use CDP to discover a Cisco device. Then it will use SNMP to get the device details. Make sure all the devices in question have CDP turned on. Some devices like a PIX do not support CDP and you need to add them yourself. Check the the VPN gateway supports CDP