I had the same problem at first. I am running ESXi with SNMP enabled so it should be similar to yours. I set this up, remodeled the devices several times and tried various other things. The process that fixed it for me is this (may be difficult in productions environments):

1. Remove the device from Zenoss

2. Restart Zope

3. Add the device back to Zenoss directly into the /Devices/Server/ESX Class

4. Remodel the device

I am not sure why this fixed it, but it is what did it for me.

After installing NetSNMP and running check_esx2, I get this error ... Error: No VMWare SNMP ub-agent running (vmware-snmpd) ... Can someone tell me what this is?

It looks like we are running ESX from what I see in the ESX name in vSphere.

SNMP was configured on the ESX but the sub-agent is not.

I was able to snmpwalk to the device using OID 1.3.6.1.4.1 but not to 1.3.6.1.4.1.6876.

The PDF linked is very helpful.

Thank you for the help. We will configure the SNMP sub-agent and test.

- Ken