ERROR: job failed with err -16 - Device or resource busy. Promox backup fails randomly every other week

[Geek]

For some reason a VM is not being backed up at random times. It fails towards the end. I have the latest proxmox (7.0-10).

Following is the status log:

()
INFO: starting new backup job: vzdump 100 --storage vm_backup --mailnotification always --mode snapshot --compress zstd --quiet 1
INFO: Starting Backup of VM 100 (qemu)
INFO: Backup started at 2021-09-10 21:00:01
INFO: status = running
INFO: VM Name: Win-10-Pro
INFO: include disk 'scsi0' 'new_vm_disk:100/vm-100-disk-0.raw' 120G
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: creating vzdump archive '/mnt/pve/vm_backup/dump/vzdump-qemu-100-2021_09_10-21_00_01.vma.zst'
INFO: issuing guest-agent 'fs-freeze' command
INFO: issuing guest-agent 'fs-thaw' command
INFO: started backup task '30c8ad81-cf60-4616-a048-5093a2396088'
INFO: resuming VM again
INFO:   0% (184.9 MiB of 120.0 GiB) in 3s, read: 61.6 MiB/s, write: 42.1 MiB/s
INFO:   1% (1.2 GiB of 120.0 GiB) in 25s, read: 48.8 MiB/s, write: 45.0 MiB/s
INFO:   2% (2.4 GiB of 120.0 GiB) in 57s, read: 37.9 MiB/s, write: 37.3 MiB/s
INFO:   3% (3.6 GiB of 120.0 GiB) in 1m 30s, read: 37.0 MiB/s, write: 36.5 MiB/s
INFO:   4% (4.8 GiB of 120.0 GiB) in 2m, read: 41.1 MiB/s, write: 40.5 MiB/s
INFO:   5% (6.0 GiB of 120.0 GiB) in 2m 29s, read: 43.1 MiB/s, write: 42.7 MiB/s
INFO:   6% (7.2 GiB of 120.0 GiB) in 2m 59s, read: 41.1 MiB/s, write: 40.7 MiB/s
INFO:   7% (8.4 GiB of 120.0 GiB) in 3m 28s, read: 41.2 MiB/s, write: 41.1 MiB/s
INFO:   8% (9.6 GiB of 120.0 GiB) in 3m 59s, read: 39.6 MiB/s, write: 39.5 MiB/s
INFO:   9% (10.8 GiB of 120.0 GiB) in 4m 27s, read: 44.0 MiB/s, write: 39.7 MiB/s
INFO:  10% (12.0 GiB of 120.0 GiB) in 4m 57s, read: 42.3 MiB/s, write: 42.1 MiB/s
INFO:  11% (13.2 GiB of 120.0 GiB) in 5m 25s, read: 42.7 MiB/s, write: 42.1 MiB/s
INFO:  12% (14.4 GiB of 120.0 GiB) in 5m 58s, read: 36.8 MiB/s, write: 36.8 MiB/s
INFO:  13% (15.8 GiB of 120.0 GiB) in 6m 28s, read: 47.4 MiB/s, write: 5.9 MiB/s
INFO:  14% (17.0 GiB of 120.0 GiB) in 6m 55s, read: 47.3 MiB/s, write: 2.4 KiB/s
INFO:  15% (18.1 GiB of 120.0 GiB) in 7m 19s, read: 47.4 MiB/s, write: 8.0 KiB/s
INFO:  16% (19.3 GiB of 120.0 GiB) in 7m 39s, read: 57.6 MiB/s, write: 25.6 KiB/s
INFO:  17% (20.4 GiB of 120.0 GiB) in 8m 2s, read: 50.6 MiB/s, write: 50.3 MiB/s
INFO:  18% (21.6 GiB of 120.0 GiB) in 8m 32s, read: 41.4 MiB/s, write: 41.4 MiB/s
INFO:  19% (22.8 GiB of 120.0 GiB) in 9m 3s, read: 40.5 MiB/s, write: 40.4 MiB/s
INFO:  20% (24.0 GiB of 120.0 GiB) in 9m 32s, read: 41.8 MiB/s, write: 41.6 MiB/s
INFO:  21% (25.2 GiB of 120.0 GiB) in 10m 1s, read: 42.2 MiB/s, write: 42.1 MiB/s
INFO:  22% (26.4 GiB of 120.0 GiB) in 10m 32s, read: 40.0 MiB/s, write: 40.0 MiB/s
INFO:  23% (27.7 GiB of 120.0 GiB) in 10m 53s, read: 59.9 MiB/s, write: 59.9 MiB/s
INFO:  24% (28.8 GiB of 120.0 GiB) in 11m 18s, read: 47.8 MiB/s, write: 47.8 MiB/s
INFO:  25% (30.0 GiB of 120.0 GiB) in 11m 47s, read: 42.5 MiB/s, write: 42.5 MiB/s
INFO:  26% (31.2 GiB of 120.0 GiB) in 12m 16s, read: 41.9 MiB/s, write: 41.9 MiB/s
INFO:  27% (32.5 GiB of 120.0 GiB) in 12m 38s, read: 57.2 MiB/s, write: 57.2 MiB/s
INFO:  28% (33.6 GiB of 120.0 GiB) in 13m 1s, read: 51.4 MiB/s, write: 51.4 MiB/s
INFO:  29% (34.8 GiB of 120.0 GiB) in 13m 30s, read: 42.9 MiB/s, write: 42.8 MiB/s
INFO:  30% (36.0 GiB of 120.0 GiB) in 13m 56s, read: 47.4 MiB/s, write: 47.4 MiB/s
INFO:  31% (37.2 GiB of 120.0 GiB) in 14m 17s, read: 58.0 MiB/s, write: 57.9 MiB/s
INFO:  32% (38.4 GiB of 120.0 GiB) in 14m 46s, read: 42.5 MiB/s, write: 42.5 MiB/s
INFO:  33% (39.6 GiB of 120.0 GiB) in 15m 14s, read: 44.7 MiB/s, write: 44.7 MiB/s
INFO:  34% (40.8 GiB of 120.0 GiB) in 15m 35s, read: 57.5 MiB/s, write: 57.5 MiB/s
INFO:  35% (42.0 GiB of 120.0 GiB) in 16m, read: 49.3 MiB/s, write: 49.3 MiB/s
INFO:  36% (43.2 GiB of 120.0 GiB) in 16m 22s, read: 56.0 MiB/s, write: 56.0 MiB/s
INFO:  37% (44.4 GiB of 120.0 GiB) in 16m 45s, read: 53.6 MiB/s, write: 53.6 MiB/s
INFO:  38% (45.6 GiB of 120.0 GiB) in 17m 5s, read: 62.5 MiB/s, write: 62.5 MiB/s
INFO:  39% (46.8 GiB of 120.0 GiB) in 17m 30s, read: 48.6 MiB/s, write: 48.5 MiB/s
INFO:  40% (48.0 GiB of 120.0 GiB) in 17m 49s, read: 63.9 MiB/s, write: 63.9 MiB/s
INFO:  41% (49.3 GiB of 120.0 GiB) in 18m 14s, read: 50.8 MiB/s, write: 50.7 MiB/s
INFO:  42% (50.5 GiB of 120.0 GiB) in 18m 35s, read: 58.5 MiB/s, write: 58.5 MiB/s
INFO:  43% (51.7 GiB of 120.0 GiB) in 19m 3s, read: 44.0 MiB/s, write: 43.9 MiB/s
INFO:  44% (52.8 GiB of 120.0 GiB) in 19m 27s, read: 49.7 MiB/s, write: 49.4 MiB/s
INFO:  45% (54.0 GiB of 120.0 GiB) in 19m 59s, read: 38.5 MiB/s, write: 37.8 MiB/s
INFO:  46% (55.2 GiB of 120.0 GiB) in 20m 21s, read: 55.9 MiB/s, write: 55.0 MiB/s
INFO:  47% (56.4 GiB of 120.0 GiB) in 20m 53s, read: 38.1 MiB/s, write: 38.1 MiB/s
INFO:  48% (57.7 GiB of 120.0 GiB) in 21m 22s, read: 43.8 MiB/s, write: 43.7 MiB/s
INFO:  49% (58.8 GiB of 120.0 GiB) in 21m 43s, read: 56.4 MiB/s, write: 56.4 MiB/s
INFO:  50% (60.0 GiB of 120.0 GiB) in 22m 14s, read: 40.3 MiB/s, write: 40.3 MiB/s
INFO:  51% (61.2 GiB of 120.0 GiB) in 22m 45s, read: 39.3 MiB/s, write: 37.1 MiB/s
INFO:  52% (62.4 GiB of 120.0 GiB) in 23m 9s, read: 51.7 MiB/s, write: 51.6 MiB/s
INFO:  53% (63.6 GiB of 120.0 GiB) in 23m 35s, read: 46.1 MiB/s, write: 46.1 MiB/s
INFO:  54% (64.8 GiB of 120.0 GiB) in 24m 15s, read: 31.3 MiB/s, write: 31.3 MiB/s
INFO:  55% (66.1 GiB of 120.0 GiB) in 24m 47s, read: 39.0 MiB/s, write: 39.0 MiB/s
INFO:  56% (67.2 GiB of 120.0 GiB) in 25m 12s, read: 47.7 MiB/s, write: 47.7 MiB/s
INFO:  57% (68.4 GiB of 120.0 GiB) in 25m 49s, read: 33.4 MiB/s, write: 33.4 MiB/s
INFO:  58% (69.6 GiB of 120.0 GiB) in 26m 11s, read: 55.7 MiB/s, write: 55.7 MiB/s
INFO:  59% (70.8 GiB of 120.0 GiB) in 26m 44s, read: 38.1 MiB/s, write: 38.1 MiB/s
INFO:  60% (72.0 GiB of 120.0 GiB) in 27m 8s, read: 50.6 MiB/s, write: 50.6 MiB/s
INFO:  61% (73.2 GiB of 120.0 GiB) in 27m 39s, read: 39.2 MiB/s, write: 39.2 MiB/s
INFO:  62% (74.4 GiB of 120.0 GiB) in 27m 59s, read: 61.6 MiB/s, write: 61.6 MiB/s
INFO:  63% (75.6 GiB of 120.0 GiB) in 28m 27s, read: 43.5 MiB/s, write: 43.4 MiB/s
INFO:  64% (76.9 GiB of 120.0 GiB) in 28m 57s, read: 42.3 MiB/s, write: 42.1 MiB/s
INFO:  65% (78.1 GiB of 120.0 GiB) in 29m 20s, read: 53.7 MiB/s, write: 53.5 MiB/s
INFO:  66% (79.2 GiB of 120.0 GiB) in 29m 55s, read: 34.6 MiB/s, write: 34.6 MiB/s
INFO:  67% (80.4 GiB of 120.0 GiB) in 30m 22s, read: 44.2 MiB/s, write: 44.2 MiB/s
INFO:  68% (81.6 GiB of 120.0 GiB) in 31m 1s, read: 31.8 MiB/s, write: 31.8 MiB/s
INFO:  69% (82.8 GiB of 120.0 GiB) in 31m 26s, read: 48.7 MiB/s, write: 48.7 MiB/s
INFO:  70% (84.0 GiB of 120.0 GiB) in 31m 57s, read: 40.9 MiB/s, write: 40.9 MiB/s
INFO:  71% (85.2 GiB of 120.0 GiB) in 32m 18s, read: 58.5 MiB/s, write: 58.5 MiB/s
INFO:  72% (86.4 GiB of 120.0 GiB) in 32m 51s, read: 35.9 MiB/s, write: 35.9 MiB/s
INFO:  73% (87.6 GiB of 120.0 GiB) in 33m 13s, read: 57.0 MiB/s, write: 57.0 MiB/s
INFO:  74% (88.8 GiB of 120.0 GiB) in 33m 37s, read: 51.8 MiB/s, write: 51.8 MiB/s
INFO:  75% (90.0 GiB of 120.0 GiB) in 33m 58s, read: 58.7 MiB/s, write: 58.7 MiB/s
INFO:  76% (91.2 GiB of 120.0 GiB) in 34m 22s, read: 50.4 MiB/s, write: 50.4 MiB/s
INFO:  77% (92.5 GiB of 120.0 GiB) in 34m 47s, read: 50.8 MiB/s, write: 50.8 MiB/s
INFO:  78% (93.7 GiB of 120.0 GiB) in 35m 9s, read: 55.9 MiB/s, write: 55.9 MiB/s
INFO:  79% (94.9 GiB of 120.0 GiB) in 35m 34s, read: 49.3 MiB/s, write: 49.3 MiB/s
INFO:  80% (96.0 GiB of 120.0 GiB) in 35m 58s, read: 49.1 MiB/s, write: 49.1 MiB/s
INFO:  81% (97.2 GiB of 120.0 GiB) in 36m 23s, read: 48.6 MiB/s, write: 48.6 MiB/s
INFO:  82% (98.4 GiB of 120.0 GiB) in 36m 43s, read: 63.4 MiB/s, write: 28.7 MiB/s
INFO:  83% (99.6 GiB of 120.0 GiB) in 37m 6s, read: 51.9 MiB/s, write: 51.7 MiB/s
INFO:  84% (100.8 GiB of 120.0 GiB) in 37m 38s, read: 39.1 MiB/s, write: 39.1 MiB/s
INFO:  84% (101.0 GiB of 120.0 GiB) in 37m 46s, read: 24.8 MiB/s, write: 24.8 MiB/s
ERROR: job failed with err -16 - Device or resource busy
INFO: aborting backup job
INFO: resuming VM again
ERROR: Backup of VM 100 failed - job failed with err -16 - Device or resource busy
INFO: Failed at 2021-09-10 21:37:59
INFO: Backup job finished with errors

TASK ERROR: job errors

All other backup failures have either occurred at 84%, 13% or 15% with the exact same error "ERROR: job failed with err -16 - Device or resource busy"
It is a windows 10 VM

 

[co-creater]

Hi, I am having the same issue with Proxmox v8.1.10 and PBS v3.1-5.

I have a datastore added via CIFS which is hosted by a QNAP NAS (TS-451) in the same LAN as the PBS instance. I can backup all my VMs and LXCs without any issue besides one VM which is quite big cimpared to the other VMs. It is an Open Mediavault instance hosting ~ 2 TB but offers up to 4 TB. The process runs through to 100% and then fails.
The PBS instance is hosted as VM inside my Proxmox instance.

INFO: starting new backup job: vzdump 101 102 104 105 107 --notification-mode legacy-sendmail --storage PBS_Datenheini --quiet 1 --mailnotification failure --mailto oliver.r.eckstein@gmail.com --notes-template '{{guestname}}' --mode snapshot
INFO: Starting Backup of VM 101 (qemu)
INFO: Backup started at 2024-06-08 03:00:02
INFO: status = running
INFO: VM Name: openmediavault
INFO: include disk 'scsi0' 'local-lvm:vm-101-disk-0' 8G
INFO: include disk 'virtio0' 'raid10:vm-101-disk-0' 4T
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: creating Proxmox Backup Server archive 'vm/101/2024-06-08T01:00:02Z'
INFO: started backup task 'c70ac89a-9087-43bf-98fa-b3e073197161'
INFO: resuming VM again
INFO: scsi0: dirty-bitmap status: existing bitmap was invalid and has been cleared
INFO: virtio0: dirty-bitmap status: existing bitmap was invalid and has been cleared
INFO:   0% (468.0 MiB of 4.0 TiB) in 3s, read: 156.0 MiB/s, write: 146.7 MiB/s
INFO:   1% (41.1 GiB of 4.0 TiB) in 16m 26s, read: 42.3 MiB/s, write: 40.9 MiB/s
INFO:   2% (82.1 GiB of 4.0 TiB) in 33m 16s, read: 41.6 MiB/s, write: 38.4 MiB/s
INFO:   3% (123.1 GiB of 4.0 TiB) in 44m 52s, read: 60.4 MiB/s, write: 35.6 MiB/s
INFO:   4% (164.2 GiB of 4.0 TiB) in 1h 1m 27s, read: 42.3 MiB/s, write: 40.3 MiB/s
INFO:   5% (205.2 GiB of 4.0 TiB) in 1h 15m 46s, read: 48.9 MiB/s, write: 46.3 MiB/s
INFO:   6% (246.3 GiB of 4.0 TiB) in 1h 30m 6s, read: 48.9 MiB/s, write: 46.6 MiB/s
INFO:   7% (287.3 GiB of 4.0 TiB) in 1h 44m 15s, read: 49.5 MiB/s, write: 47.9 MiB/s
INFO:   8% (330.3 GiB of 4.0 TiB) in 1h 48m 55s, read: 157.0 MiB/s, write: 49.8 MiB/s
INFO:   9% (370.9 GiB of 4.0 TiB) in 1h 59m 18s, read: 66.7 MiB/s, write: 49.7 MiB/s
INFO:  10% (410.7 GiB of 4.0 TiB) in 1h 59m 49s, read: 1.3 GiB/s, write: 33.5 MiB/s
INFO:  11% (451.6 GiB of 4.0 TiB) in 2h 1m 6s, read: 544.1 MiB/s, write: 50.2 MiB/s
INFO:  12% (494.4 GiB of 4.0 TiB) in 2h 1m 35s, read: 1.5 GiB/s, write: 27.3 MiB/s
INFO:  13% (533.9 GiB of 4.0 TiB) in 2h 6m 49s, read: 128.9 MiB/s, write: 51.1 MiB/s
INFO:  14% (574.7 GiB of 4.0 TiB) in 2h 10m 2s, read: 216.2 MiB/s, write: 49.5 MiB/s
INFO:  15% (615.6 GiB of 4.0 TiB) in 2h 18m 14s, read: 85.2 MiB/s, write: 49.6 MiB/s
INFO:  16% (656.8 GiB of 4.0 TiB) in 2h 24m 12s, read: 117.7 MiB/s, write: 50.6 MiB/s
INFO:  17% (697.7 GiB of 4.0 TiB) in 2h 32m 16s, read: 86.6 MiB/s, write: 51.1 MiB/s
INFO:  18% (738.8 GiB of 4.0 TiB) in 2h 40m 21s, read: 86.7 MiB/s, write: 51.7 MiB/s
INFO:  19% (779.8 GiB of 4.0 TiB) in 2h 50m 40s, read: 67.8 MiB/s, write: 52.4 MiB/s
INFO:  20% (821.5 GiB of 4.0 TiB) in 3h 48s, read: 70.2 MiB/s, write: 33.6 MiB/s
INFO:  21% (864.1 GiB of 4.0 TiB) in 3h 2m 55s, read: 344.0 MiB/s, write: 54.1 MiB/s
INFO:  22% (902.9 GiB of 4.0 TiB) in 3h 7m 12s, read: 154.6 MiB/s, write: 56.4 MiB/s
INFO:  23% (944.3 GiB of 4.0 TiB) in 3h 13m 8s, read: 119.1 MiB/s, write: 58.0 MiB/s
INFO:  24% (985.4 GiB of 4.0 TiB) in 3h 13m 35s, read: 1.5 GiB/s, write: 26.1 MiB/s
INFO:  25% (1.0 TiB of 4.0 TiB) in 3h 14m 2s, read: 1.6 GiB/s, write: 29.2 MiB/s
INFO:  26% (1.0 TiB of 4.0 TiB) in 3h 14m 24s, read: 1.8 GiB/s, write: 23.8 MiB/s
INFO:  27% (1.1 TiB of 4.0 TiB) in 3h 14m 51s, read: 1.6 GiB/s, write: 29.2 MiB/s
INFO:  28% (1.1 TiB of 4.0 TiB) in 3h 15m 12s, read: 1.9 GiB/s, write: 25.3 MiB/s
INFO:  29% (1.2 TiB of 4.0 TiB) in 3h 15m 38s, read: 1.5 GiB/s, write: 30.0 MiB/s
INFO:  30% (1.2 TiB of 4.0 TiB) in 3h 16m, read: 1.9 GiB/s, write: 23.8 MiB/s
INFO:  31% (1.2 TiB of 4.0 TiB) in 3h 16m 27s, read: 1.6 GiB/s, write: 29.0 MiB/s
INFO:  32% (1.3 TiB of 4.0 TiB) in 3h 16m 53s, read: 1.5 GiB/s, write: 30.3 MiB/s
INFO:  33% (1.3 TiB of 4.0 TiB) in 3h 17m 16s, read: 1.9 GiB/s, write: 23.1 MiB/s
INFO:  34% (1.4 TiB of 4.0 TiB) in 3h 17m 42s, read: 1.5 GiB/s, write: 30.5 MiB/s
INFO:  35% (1.4 TiB of 4.0 TiB) in 3h 18m 4s, read: 1.9 GiB/s, write: 24.2 MiB/s
INFO:  36% (1.4 TiB of 4.0 TiB) in 3h 18m 30s, read: 1.5 GiB/s, write: 30.3 MiB/s
INFO:  37% (1.5 TiB of 4.0 TiB) in 3h 18m 52s, read: 1.9 GiB/s, write: 24.0 MiB/s
INFO:  38% (1.5 TiB of 4.0 TiB) in 3h 21m 47s, read: 237.2 MiB/s, write: 55.3 MiB/s
INFO:  39% (1.6 TiB of 4.0 TiB) in 3h 22m 10s, read: 1.7 GiB/s, write: 34.1 MiB/s
INFO:  40% (1.6 TiB of 4.0 TiB) in 3h 22m 36s, read: 1.7 GiB/s, write: 20.3 MiB/s
INFO:  41% (1.6 TiB of 4.0 TiB) in 3h 23m 4s, read: 1.5 GiB/s, write: 28.0 MiB/s
INFO:  42% (1.7 TiB of 4.0 TiB) in 3h 23m 24s, read: 2.0 GiB/s, write: 20.0 MiB/s
INFO:  43% (1.7 TiB of 4.0 TiB) in 3h 23m 50s, read: 1.5 GiB/s, write: 30.2 MiB/s
INFO:  44% (1.8 TiB of 4.0 TiB) in 3h 24m 12s, read: 1.9 GiB/s, write: 23.6 MiB/s
INFO:  45% (1.8 TiB of 4.0 TiB) in 3h 24m 38s, read: 1.5 GiB/s, write: 30.3 MiB/s
INFO:  46% (1.8 TiB of 4.0 TiB) in 3h 25m, read: 1.8 GiB/s, write: 29.1 MiB/s
INFO:  47% (1.9 TiB of 4.0 TiB) in 3h 32m 52s, read: 88.2 MiB/s, write: 52.8 MiB/s
INFO:  48% (1.9 TiB of 4.0 TiB) in 3h 45m 56s, read: 53.6 MiB/s, write: 52.6 MiB/s
INFO:  49% (2.0 TiB of 4.0 TiB) in 3h 59m 2s, read: 53.4 MiB/s, write: 52.5 MiB/s
INFO:  50% (2.0 TiB of 4.0 TiB) in 4h 10m 28s, read: 63.2 MiB/s, write: 54.0 MiB/s
INFO:  51% (2.0 TiB of 4.0 TiB) in 4h 10m 50s, read: 1.9 GiB/s, write: 24.0 MiB/s
INFO:  52% (2.1 TiB of 4.0 TiB) in 4h 11m 17s, read: 1.6 GiB/s, write: 29.2 MiB/s
INFO:  53% (2.1 TiB of 4.0 TiB) in 4h 16m 4s, read: 136.8 MiB/s, write: 53.8 MiB/s
INFO:  54% (2.2 TiB of 4.0 TiB) in 4h 31m 31s, read: 45.3 MiB/s, write: 41.7 MiB/s
INFO:  55% (2.2 TiB of 4.0 TiB) in 4h 47m 30s, read: 43.8 MiB/s, write: 41.8 MiB/s
INFO:  56% (2.2 TiB of 4.0 TiB) in 4h 59m 57s, read: 56.3 MiB/s, write: 55.6 MiB/s
INFO:  57% (2.3 TiB of 4.0 TiB) in 5h 11m 56s, read: 58.4 MiB/s, write: 56.9 MiB/s
INFO:  58% (2.3 TiB of 4.0 TiB) in 5h 23m 52s, read: 58.7 MiB/s, write: 57.7 MiB/s
INFO:  59% (2.4 TiB of 4.0 TiB) in 5h 35m 41s, read: 59.3 MiB/s, write: 58.0 MiB/s
INFO:  60% (2.4 TiB of 4.0 TiB) in 5h 47m 42s, read: 58.4 MiB/s, write: 57.4 MiB/s
INFO:  61% (2.4 TiB of 4.0 TiB) in 5h 59m 27s, read: 59.6 MiB/s, write: 58.7 MiB/s
INFO:  62% (2.5 TiB of 4.0 TiB) in 6h 17m 38s, read: 38.5 MiB/s, write: 38.0 MiB/s
INFO:  63% (2.5 TiB of 4.0 TiB) in 6h 36m 18s, read: 37.5 MiB/s, write: 37.0 MiB/s
INFO:  64% (2.6 TiB of 4.0 TiB) in 6h 48m 20s, read: 58.3 MiB/s, write: 57.4 MiB/s
INFO:  65% (2.6 TiB of 4.0 TiB) in 7h 3m 12s, read: 47.1 MiB/s, write: 44.5 MiB/s
INFO:  66% (2.6 TiB of 4.0 TiB) in 7h 14m 53s, read: 59.9 MiB/s, write: 58.3 MiB/s
INFO:  67% (2.7 TiB of 4.0 TiB) in 7h 26m 15s, read: 61.6 MiB/s, write: 58.7 MiB/s
INFO:  68% (2.7 TiB of 4.0 TiB) in 7h 31m 54s, read: 124.0 MiB/s, write: 57.5 MiB/s
INFO:  69% (2.8 TiB of 4.0 TiB) in 7h 43m 40s, read: 59.5 MiB/s, write: 56.2 MiB/s
INFO:  70% (2.8 TiB of 4.0 TiB) in 7h 55m 1s, read: 61.6 MiB/s, write: 56.7 MiB/s
INFO:  71% (2.8 TiB of 4.0 TiB) in 8h 5m 19s, read: 68.4 MiB/s, write: 57.7 MiB/s
INFO:  72% (2.9 TiB of 4.0 TiB) in 8h 16m 23s, read: 62.9 MiB/s, write: 55.3 MiB/s
INFO:  73% (2.9 TiB of 4.0 TiB) in 8h 28m 23s, read: 58.4 MiB/s, write: 55.0 MiB/s
INFO:  74% (3.0 TiB of 4.0 TiB) in 8h 40m 10s, read: 59.6 MiB/s, write: 56.0 MiB/s
INFO:  75% (3.0 TiB of 4.0 TiB) in 8h 50m 46s, read: 65.8 MiB/s, write: 55.5 MiB/s
INFO:  76% (3.0 TiB of 4.0 TiB) in 9h 2m 22s, read: 60.5 MiB/s, write: 56.1 MiB/s
INFO:  77% (3.1 TiB of 4.0 TiB) in 9h 13m 14s, read: 64.4 MiB/s, write: 56.3 MiB/s
INFO:  78% (3.1 TiB of 4.0 TiB) in 9h 24m 27s, read: 62.5 MiB/s, write: 56.9 MiB/s
INFO:  79% (3.2 TiB of 4.0 TiB) in 9h 35m 41s, read: 62.3 MiB/s, write: 58.6 MiB/s
INFO:  80% (3.2 TiB of 4.0 TiB) in 9h 47m 11s, read: 60.9 MiB/s, write: 57.1 MiB/s
INFO:  81% (3.2 TiB of 4.0 TiB) in 10h 2m 19s, read: 46.3 MiB/s, write: 43.6 MiB/s
INFO:  82% (3.3 TiB of 4.0 TiB) in 10h 13m 54s, read: 60.4 MiB/s, write: 56.7 MiB/s
INFO:  83% (3.3 TiB of 4.0 TiB) in 10h 25m 14s, read: 61.8 MiB/s, write: 58.2 MiB/s
INFO:  84% (3.4 TiB of 4.0 TiB) in 10h 36m 42s, read: 61.0 MiB/s, write: 57.2 MiB/s
INFO:  85% (3.4 TiB of 4.0 TiB) in 10h 45m 42s, read: 78.1 MiB/s, write: 60.4 MiB/s
INFO:  86% (3.4 TiB of 4.0 TiB) in 10h 47m 8s, read: 502.8 MiB/s, write: 52.0 MiB/s
INFO:  87% (3.5 TiB of 4.0 TiB) in 10h 47m 33s, read: 1.7 GiB/s, write: 31.5 MiB/s
INFO:  88% (3.5 TiB of 4.0 TiB) in 10h 47m 54s, read: 2.0 GiB/s, write: 25.1 MiB/s
INFO:  89% (3.6 TiB of 4.0 TiB) in 10h 48m 20s, read: 1.5 GiB/s, write: 30.3 MiB/s
INFO:  90% (3.6 TiB of 4.0 TiB) in 10h 48m 40s, read: 2.0 GiB/s, write: 26.4 MiB/s
INFO:  91% (3.6 TiB of 4.0 TiB) in 10h 49m 5s, read: 1.6 GiB/s, write: 31.7 MiB/s
INFO:  92% (3.7 TiB of 4.0 TiB) in 10h 49m 26s, read: 1.9 GiB/s, write: 25.1 MiB/s
INFO:  93% (3.7 TiB of 4.0 TiB) in 10h 49m 52s, read: 1.7 GiB/s, write: 30.2 MiB/s
INFO:  94% (3.8 TiB of 4.0 TiB) in 10h 50m 17s, read: 1.5 GiB/s, write: 31.7 MiB/s
INFO:  95% (3.8 TiB of 4.0 TiB) in 10h 50m 38s, read: 2.0 GiB/s, write: 25.1 MiB/s
INFO:  96% (3.8 TiB of 4.0 TiB) in 10h 51m 3s, read: 1.6 GiB/s, write: 31.5 MiB/s
INFO:  97% (3.9 TiB of 4.0 TiB) in 10h 51m 24s, read: 2.0 GiB/s, write: 25.1 MiB/s
INFO:  98% (3.9 TiB of 4.0 TiB) in 10h 51m 49s, read: 1.6 GiB/s, write: 31.5 MiB/s
INFO:  99% (4.0 TiB of 4.0 TiB) in 10h 52m 11s, read: 1.8 GiB/s, write: 25.3 MiB/s
INFO: 100% (4.0 TiB of 4.0 TiB) in 10h 54m 3s, read: 364.1 MiB/s, write: 63.2 MiB/s
ERROR: backup finish failed: command error: error during syncfs: Device or resource busy (os error 16)
INFO: aborting backup job
INFO: resuming VM again
ERROR: Backup of VM 101 failed - backup finish failed: command error: error during syncfs: Device or resource busy (os error 16)
INFO: Failed at 2024-06-08 13:54:05

What is a bit weird: The backups on this exact same NAS worked when I did the following in the past:

• Proxmox host mounts the QNAP NAS via CIFS
• This share gets mounted as a drive into the PBS
• The datastore is placed on that drive

This lead to one 4 TB big file on the NAS and all backups ran through. However, I did not like that approach as it could have created issues in case I lost the Proxmox instance. In this thread a better approach was discussed which I will implement. However, it still requires mounting the NAS via CIFS into the PBS and use it as a datastore. Any idea?