This is by no means a new issue. However, I still get support calls regarding tasks that get stuck on VMs. What do I mean by "stuck tasks"? Well, I've seen cases where a snapshot task initiated by VCB got stuck in the state of "Creating Virtual Machine Snapshot". Then VM goes down and cannot be accessed via the console, does not respond to pings, and the status of VMtools turns to "Unknown". You also cannot do "Power On" on the VM either as the "Creating Virtual Machine Snapshot" task is still showing as an active task. You can wait, but after 30 minutes, chances are that it won't sort itself out, so user intervention is required!

This is normally the approuch I take to sort this out:

1. Make sure that the VM is inaccessible to everyone and that it really is down.

2. Browse the datastore where the VM is located (best to do this via the CLI on the service console with "ls -lh") and check the time stamps of the files to see how log the snapshots, if any,have been sitting there for.
3. in VirtualCenter, or "vCenter" the VM will probably still be showing as powered on. Check on which of your ESX hosts it is running.
4. Log onto the service console of the ESX host that is running the VM. Elevate your priviledges to root.
5. Now, as the VM has an active task, you won't be able to send any other commands to the VM. You won't be able to use vmware-cmd to change the state of the VM either. Until the task that's stuck in progress has completed, the ESX host will not be able to send any power commands to the VM. The only way to now release the VM from it's sorry state and get rid of the "Active task" is to kill the VM's running process from the service console. In order to do so, you need to find the PID for the "running" VM. To get the PID do:

The Syntax is:
ps -auxwww |grep <VM-NAME>

Example:
Suppose you have a VM called WKSTNL01 The command will be:
ps -auxwww |grep WKSTNL01


This should return something like this:

root     12322  0.0  0.4   3140  1320 ?        S<s  13:32   0:03 /usr/lib/vmware/bin/vmkload_app --sched.group=host/user/pool1 /usr/lib/vmware/bin/vmware-vmx -ssched.group=host/user/pool1 -# name=VMware ESX;version=4.0.0;buildnumber=164009;licensename=VMware ESX Server;licenseversion=4.0 build-164009; -@ pipe=/tmp/vmhsdaemon-0/vmx673aca8b7403868b; /vmfs/volumes/489a1228-2bfd25b5-6a2c-000e0cc41e52/WKSTNL01/WKSTNL01.vmx

The PID in this instance is 12322. This is what we need to kill.

6. Kill the process ID with kill -9:

kill -9 12322


7. Delete any snapshots created

8. Power On the VM.

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