CRC error when trying to restore VM from an NFS mount

[gecko64]

Hello, i've updated my Proxmox few days ago to the version 6.1-8.
For a reason, i've decided to restore a VM under Debian 10 and which host some webservices.
The NFS run under Debian 9 and is directly into the same local network.

During the restoration process, i've got this :

restore vma archive: zcat /mnt/pve/backup-vm/dump/vzdump-qemu-113-2020_04_23-05_28_36.vma.gz | vma extract -v -r /var/tmp/vzdumptmp2048320.fifo - /var/tmp/vzdumptmp2048320
CFG: size: 399 name: qemu-server.conf
DEV: dev_id=1 size: 26843545600 devname: drive-sata0
CTIME: Thu Apr 23 05:28:39 2020
WARNING: You have not turned on protection against thin pools running out of space.
WARNING: Set activation/thin_pool_autoextend_threshold below 100 to trigger automatic extension of thin pools before they get full.
Logical volume "vm-113-disk-1" created.
WARNING: Sum of all thin volume sizes (282.00 GiB) exceeds the size of thin pool pve/data and the size of whole volume group (<255.92 GiB).
new volume ID is 'local-lvm:vm-113-disk-1'
map 'drive-sata0' to '/dev/pve/vm-113-disk-1' (write zeros = 0)
progress 1% (read 268435456 bytes, duration 3 sec)
progress 2% (read 536870912 bytes, duration 6 sec)
...
progress 91% (read 24427626496 bytes, duration 276 sec)
progress 92% (read 24696061952 bytes, duration 276 sec)

gzip: /mnt/pve/backup-vm/dump/vzdump-qemu-113-2020_04_23-05_28_36.vma.gz: invalid compressed data--crc error
progress 93% (read 24964497408 bytes, duration 276 sec)
progress 94% (read 25232932864 bytes, duration 276 sec)
progress 95% (read 25501368320 bytes, duration 276 sec)
progress 96% (read 25769803776 bytes, duration 276 sec)
progress 97% (read 26038239232 bytes, duration 276 sec)
progress 98% (read 26306674688 bytes, duration 276 sec)
progress 99% (read 26575110144 bytes, duration 276 sec)
progress 100% (read 26843545600 bytes, duration 276 sec)
total bytes read 26843545600, sparse bytes 12866244608 (47.9%)
space reduction due to 4K zero blocks 1.61%
Logical volume "vm-113-disk-1" successfully removed
temporary volume 'local-lvm:vm-113-disk-1' sucessfuly removed
TASK ERROR: command 'set -o pipefail && zcat /mnt/pve/backup-vm/dump/vzdump-qemu-113-2020_04_23-05_28_36.vma.gz | vma extract -v -r /var/tmp/vzdumptmp2048320.fifo - /var/tmp/vzdumptmp2048320' failed: exit code 1

No error during the automatic backup, i had the Email correctly.
So i'm wondering why i've got this crc error.
I tried with 4 différents backup of the same virtual machine and problem persist.
I don't know what to do to get my data back...

I've also checked, during the restauration until it crash, the local-lvm is not full.

No idea if someone has already met this problem ?
Thank you.

 

[wolfgang]

Hi,

this error comes from gzip.
There are three possible scenarios.
1.) Network produce errors
2.) Data on the NAS have a bitflip that can propagate if you have a Raid with Raid5 or Raid6. see data rot[1].
3.) At the creation, something goes wrong because of HW failures.

Try to extract the backup on the NAS with gzip to prove the network is not the problem and the backup extraction is working.

1.) https://en.wikipedia.org/wiki/Data_degradation