Virtual machine freezes temporarily during snapshot removal on an NFS datastore in a ESX/ESXi 4.1 (4047374)

When removing the snapshot of the virtual machine residing on the NFS storage in an ESX/ESXi 4.1 host, you may experience these symptoms:

• The virtual machine appears to be in a hung state within the console view
• The virtual machine stops responding to ping requests
• The virtual machine is inaccessible via remote desktop

This issue may occur if you are using a backup application that utilizes Changed Block Tracking (CBT) and the ctkEnabled option for the virtual machine is set to true. The virtual machine becomes unresponsive for up to 30 seconds as NFS locks on the .ctk file are changed.

This issue is resolved in ESX 4.1 patch ESX410-201104401-SG and ESXi 4.1 patch ESXi410-201104402-BG.

http://kb.vmware.com/kb/1031106

http://kb.vmware.com/kb/5962168