how to discard a large VM disk


New Member
Sep 28, 2023
once i create the virtual hard disk didn't choose discard
now i feel it will take too larg vollume for me
any command can reduce/ discard the raw file size?
method in this page
difficult to follow since VM disks already use 95% of my real HDD volume

and... can i use ZFS for ISO imag?
Last edited:
for zvol
can use
zfs get volsize
to check hows size taking
change pve VM hardware--Hardisk discard on
then, set large size zvol
zfs set refreservation=none ZFS/vm-101-disk-1
take a snapshot
zfs snapshot ZFS/vm-101-disk-1@rec
you may see the vol changed from fix size to dynamic size

will make your vm disk become dynamic
Last edited:


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