[SOLVED] Expanding Volume Passed to VM


Active Member
Dec 27, 2018
I have an Areca raid controller that I was going to pass to the VM, but I'm having issues with it the VM not being able to reboot because it isn't "releasing" the card. I am going to look into blacklisting it on the host to see if that makes a difference, but I thought, maybe I'd just pass the "disk"/volume to the VM.

I noticed when you add a disk to a VM using the qm command, it appends the current size to the entry in the config file. If I then, say, add a disk to the volume using the areca web interface, how do I go about making the VM aware that the volume is larger. Do I need to power it off, remove/add it back?

I know I have to expand it inside the VM, just not sure how to present the enlarged volume to the VM. This is why I was just going to pass the entire controller across.

Edit: I tried to simulate this and this is what I saw.

I spun Proxmox up in Hyper-V, gave it 2 disks, both 128GB. Inside Proxmox I created a Windows 2019 VM and passed the 2nd 128GB disk to it by using the command "qm set 100 -scsi0 /dev/disk/by-id/xxxx". It added a line to the conf file "scsi0: /dev/disk/by-id/xxxx,size=127GB".

I then had to power everything off so I could modify the hyper-v disk. I expanded it out to 256GB. Powered everything back up. I looked inside Windows and it has the extra, 129GB as Unallocated even though the .conf line still has the size=127GB part.

So it looks like, even though the "qm set" command added "size=xxxx" to the line, it isn't actually used?
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