We are running a couple of Windows Servers that have disks with sizes greater 8TB. Every now and then these disks have to be expanded (by about 500GB).
Is there any known limitation for doing that while the VMs are running?
I have heard both "No problem - that's supported with ESX 6.5 and up!" and "Never do that! Always shut down the VM!".
So - what's right ?
Any offical statement from VMware on that topic?
If you need an official statement, you most likely need to contact support.
Anyway, I'm not aware of issues with resizing virtual disks, if the guest OS supports it. The only exception that I'm currently aware of, is for cluster (e.g. MSFC) shared disks, which must not be expanded online.
The only issues with resizing that I'm aware of was with expanding virtual disks >2TB in vSphere 5.5, and 6.0.