Unable to take snapshot & consolidate the VM

Recently I got an issue where customer was not able to take snapshot also unable to consolidate the snapshot.

While verifying the snapshot status of VM in snapshot manager its shows no snapshot available. However, while accessing the datastore I found 30 snapshot on both the hdd attached to the VM.

I tried to consolidate the VM from snapshot manager & from ESXi cli using below command where VIMID is the VM ID which you can get from vim-cmd vmsvc/getallvms(To get vm id) command

vim-cmd vmsvc/snapshot.removeall VMID ( To consolidate the snapshot) but it again failed by giving failed status.

Next, I tried to find CID and PID status of both the HDD connected to virtual machine. You can use below command followed the path of virtual machine. (i.e /vmfs/volumes/vmname)

for i in `ls -l *.vmdk | grep -v delta | grep -v ctk | grep -v flat | awk '{print $

$i; done

As mentioned, there are 30 delta files exist on both the HDD and one first HDD I find CID and PID mismatch where delta disk 25-30 where having 0000 CID and PID and all later HDD was having consistent details.

You can verify the disk consistency by using below command.

Vmkfstools –D /vmfs/volumes/datastore/vmname/disk.vmdk

While verifying the disk consistency I found disk to be inconsistent. Now whats next ??

Now, I decided to check the vmdk consistency all from 30 to 1. Later I got I found disk consistency on vmdk 24. I decided to map the vmdk24 to the VM which is the first HDD and try to poweron, but unable to poweron.

So, Finally I decided to clone vmdk24 of first hdd of VM where i foud the disk consistent so that all the metadata get saturated and consolidated to base disk.

You can clone the disk by using command vmkfstools –I (source disk) (destination disk)

Now, I after cloing the disk tried to add the clone HDD to the VM and try to poweron. Fortunatly it works. I’m able to poweron the VM also able to take the snapshot & consolidate.

Happy Sharing… J

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