I have added hard disks to many virtual machines but never in a situation where we need to remove them. For example below with a virtual machine named "exchange1" with 3 disks. I need to remove hard disk3. The server admin will remove the drive from the Windows machine. Once that is done, I just remove hard disk3. The disks are from different datastores. Is there anything else I have to consider? This can be done when the machine is on? Also, the reclaim disk space will occur right away?
Hard disk1 (thin provision), Windows C drive
Hard disk2 (thin provision), Windows E drive
Hard disk3 (thin provision), Windows F drive
Before remove the disks from the virtual machine, make sure they are no longer used, try remove the associated letter and put them offline at Disk Management, that will avoid a possible hangs on Windows SO.
After remove the associated letter and put the disks offline, make sure no snapshot are present on that virtual machine and remove the disk from the virtual machine. To make sure space will be release, select the option Remove from virtual machine and delete files from disk. For additional information, see: Removing a harddisk from a virtual machine through the vSphere client does not release the desired s...
From Gos Server admin can perform below
Delete the partition
Change the disk to offline
From Vmware side
you can perform this while machine is powered on
Edit virtual machine
select the drive you have to delete
go with option Remove from virtual machine and delete files from disk
> Remove from virtual machine and delete files from disk
In my humble opinion that button should have never made it into the User-interface.
The most dangerous button in vSphere can destroy a full years work faster than any other traditional procedure like earthquakes , tsunamis, slegehammers, whichcraft or poison.
I highly recommend to avoid delete-from-disk option from the UI.
If that button is often used during daily work it gets too easy and then in a blink off an eye moment its too late.
This accidents are really unnecessary.
Moving those delete-candidates into a "delete-me-next-monday" directory is not a real pain - but getting used to it is the best you can do to avoid painful accidents.
That is even more important if there are any doubts wether that vmdk may have been used from any other VM or backup-tool.