[SOLVED] Resizing guest disk

[Walery]

I have a virtual machine running Windows server 2008 r2 (disk size 600 Gb) I want to reduce the size of the disk by 42 Gb.
How can i do this?
The virtual machine disk in .raw format is located in the ZFS storage

 

[Hannes Laimer]

Hey,

shrinking has to be done manually due to the risk of deleting files or destroying your system, for more information take a look at [1].

[1] https://pve.proxmox.com/wiki/Resize_disks#General_considerations

 

[aaron]

Making a disk smaller is always risky. Make sure to have a backup of the VM before you make the next steps.

Since this disk is located on a ZFS pool, what is the output of zfs get all <pool>/<path>/<to vm disk>?

In general, you want to change the volsize parameter of the zvol to the new size. Also check if the reservation property is set to some value and if it changed automatically as well.
zfs set volsize=<size>G <pool>/<vm disk>

 

[Walery]

Making a disk smaller is always risky. Make sure to have a backup of the VM before you make the next steps.

Since this disk is located on a ZFS pool, what is the output of zfs get all <pool>/<path>/<to vm disk>?

In general, you want to change the volsize parameter of the zvol to the new size. Also check if the reservation property is set to some value and if it changed automatically as well.
zfs set volsize=<size>G <pool>/<vm disk>

I didn't understand the command
zfs get all <pool> / <path> / <to vm disk>

my pool is store1
vm is 100
But what is <path>? is it a directory? my drive is not in a directory.

zfs get all store1 / <path> / to 100 disk ?

 

[aaron]

Most likely it will be <pool>/<vm disk> but ZFS can have nested datasets which would then lead to a deeper hierarchy.

 

[Walery]

Most likely it will be <pool>/<vm disk> but ZFS can have nested datasets which would then lead to a deeper hierarchy.

zfs get all
store1/vm-100-disk-0 type volume -
store1/vm-100-disk-0 creation Mon Mar 1 13:46 2021 -
store1/vm-100-disk-0 used 891G -
store1/vm-100-disk-0 available 1.73T -
store1/vm-100-disk-0 referenced 376G -
store1/vm-100-disk-0 compressratio 1.41x -
store1/vm-100-disk-0 reservation none default
store1/vm-100-disk-0 volsize 600G local
store1/vm-100-disk-0 volblocksize 8K default
store1/vm-100-disk-0 checksum on default
store1/vm-100-disk-0 compression on inherited from store1
store1/vm-100-disk-0 readonly off default
store1/vm-100-disk-0 createtxg 80378 -
store1/vm-100-disk-0 copies 1 default
store1/vm-100-disk-0 refreservation 891G local
store1/vm-100-disk-0 guid 2778877911890891769 -
store1/vm-100-disk-0 primarycache all default
store1/vm-100-disk-0 secondarycache all default
store1/vm-100-disk-0 usedbysnapshots 0B -
store1/vm-100-disk-0 usedbydataset 376G -
store1/vm-100-disk-0 usedbychildren 0B -
store1/vm-100-disk-0 usedbyrefreservation 516G -
store1/vm-100-disk-0 logbias latency default
store1/vm-100-disk-0 objsetid 4195 -
store1/vm-100-disk-0 dedup off default
store1/vm-100-disk-0 mlslabel none default
store1/vm-100-disk-0 sync standard default
store1/vm-100-disk-0 refcompressratio 1.41x -
store1/vm-100-disk-0 written 376G -
store1/vm-100-disk-0 logicalused 365G -
store1/vm-100-disk-0 logicalreferenced 365G -
store1/vm-100-disk-0 volmode default default
store1/vm-100-disk-0 snapshot_limit none default
store1/vm-100-disk-0 snapshot_count none default
store1/vm-100-disk-0 snapdev hidden default
store1/vm-100-disk-0 context none default
store1/vm-100-disk-0 fscontext none default
store1/vm-100-disk-0 defcontext none default
store1/vm-100-disk-0 rootcontext none default
store1/vm-100-disk-0 redundant_metadata all default
store1/vm-100-disk-0 encryption off default
store1/vm-100-disk-0 keylocation none default
store1/vm-100-disk-0 keyformat none default
store1/vm-100-disk-0 pbkdf2iters 0 default

 

[aaron]

You will have to set the volsize propery to the newer, smaller value.

zfs set volsize=<size>G store1/vm-100-disk-0

I recommend set it 1 or 2 GB larger just to avoid any accounting differences causing problems. If you then start the VM again, it should see the disk being smaller

 

[Walery]

You will have to set the volsize propery to the newer, smaller value.

zfs set volsize=<size>G store1/vm-100-disk-0

I recommend set it 1 or 2 GB larger just to avoid any accounting differences causing problems. If you then start the VM again, it should see the disk being smaller

Fine! Everything works. Thank.