VMware has a new KB up on how to "Verify the health of ESX Server Operating System". The symptoms that the KB Article covers are:
- The ESX host seems slow
- There are a lot of errors in the log files
- Accessing the ESX host over a SSH session is slow
- Operations performed on the ESX host time out
These issues are now covered by KB Article 1004019
I had a problem in one of my DRS/HA Clusters where one ESX 3.0.2 host was unable to see an existing VMFS volume although the volume was in use by other ESX hosts in the cluster, and we confirmed that the SAN LUN zoning was done correctly.
I did have the option in the VI client to add more storage, and then select the LUN, but that would reformat the LUN and I would loose all my existing VM's on that volume.
The fix to this issue was to reset the LUN with "Resignaturing"...
Mightycare Solutions have some handy tools for ESX Server and VirtualCenter. They have tools to patch ESX Servers(ESX-Patcher) and view space used and reserved by VM's in your VC/ESX Server(StorageView), and many more. All these tools are free to download.
Have a look at: