I have just reinstalled LMS 3.0 but discovery does not locate any of my devices. I am able to successfully ping these via the Device Center but the SNMP Walk fails. I've checked the community string by running show snmp on one of the devices. The OID I have used is for the sysObjectID [.220.127.116.11.18.104.22.168].
Can anyone think of anything I should double-check or that I may have missed.
Discovery relies on SNMP access to the seed devices, so if this is not working, Discovery would be expected to fail.
Try running an SNMP debug on the device. I would not say it is really verbose, since SNMP traffic is usually not that much, unless you have many hosts polling it concurrently.
Try, 'term mon' and 'debug snmp packets' on your seed device, to verify if it is receiving the SNMP queries sent from the CiscoWorks server.
If you see no entries in the debug, then the SNMP packets are getting lost along the way. Perhaps a firewall or ACL was put in place that is dropping the traffic now.
The OID you are using should work on any device, so that part is OK.
Hope this helps.