This technique can be used to find out if any SNMP-enabled device has something interesting to share, but here I concentrate on VMware ESXi 4.1. No idea what the deal is with earlier versions.

There are quite a few blog posts out there describing how to enable the SNMP daemon on ESXi (this rather well-written one is the one I used).  However, the only information I’ve found says that the only data available is in the standard MIBs supported by most devices, giving information similar to netstat.  If that’s all there was, it ain’t particularly useful.