Restoring VZDump from backup--size is gigantic


Feb 24, 2019
I need to restore a couple of my VMs after a system crash. I have 5 days worth of VZDump backups for each VM on a backup server. I reinstalled Proxmox, and set the new node up identically to the original one--the only difference is the old hostname was PVE3 and the new one is PVE4. It's running on the same hardware, same storage sizes, etc.

When I try to restore one of my VZDump backups, it attempts to restore and then fills up the storage space. The VZDump file itself is around 21.5GB, but during the restore process it is filling up an entire 2TB RAID10 array. The restore process gets to around 34%, and then fails because it is out of space.

What am I doing wrong? I've used the VZDump restore successfully on other nodes in the past, and even on nodes with much less available storage space, I've never had a problem.

Here's what the command looks like in the command line:
Formatting '/var/lib/vz/images/103/vm-103-disk-0.qcow2', fmt=qcow2 size=136365211648 cluster_size=65536 preallocation=metadata lazy_refcounts=off refcount_bits=16
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I think I have this figured out. I ended up deleting the RAID10 array, recreated it, and made a new partition. Once I mounted that and added it back as storage in the Proxmox GUI, I was able to restore the backed up VZDump files with no problem.

One thing that I did note: before deleting and recreating the RAID10 array, it was like the local and raid10 storage was linked. When I tried to restore a backup, both of those would fill up simultaneously, even though they were separate storage devices on separate disks (and separate RAID arrays on the server itself). I'm not sure what happened there.
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