zfs property with no value.

[gpetrom]

Hi

I am testing zfs-autobackup and i was trying to see how it works in one dataset.
I have a pool storage with some datasets inside for example 100,101,102,103
So i configured the property with the following command
zfs set autobackup:offsite1=true storage/103
When i runned zfs-autobackup it started to delete snapshots on target on the other datasets.
Is this normal behavior?
Maybe zfs-autobackup would ignore datasets that has the property but they have no value inside

Thanks in advanced

[psy0rz]

Please shiw the commandline youre using and the verbose output. (Use --test to prevent it doing anything)

[gpetrom]

Thanks for the reply
I have made a test env to test it.
So i have enable daily only in storage 104

Property values
(backup) root@debian12:~# zfs get -t filesystem,volume autobackup:daily NAME PROPERTY VALUE SOURCE storage autobackup:daily - - storage/100 autobackup:daily - - storage/101 autobackup:daily - - storage/102 autobackup:daily - - storage/103 autobackup:daily - - storage/104 autobackup:daily parent local storage/105 autobackup:daily -
zfs-autobackup -v --clear-mountpoint --ssh-target debian11_test hourly storage/images --test --no-holds --strip-path=1 --keep-source=2 --keep-target=2 --min-change=0 --snapshot-format=autosnap_%Y-%m-%d_%H:%M:%S_daily --buffer 128M --utc
With --test
(backup) root@debian12:~# zfs-autobackup -v --clear-mountpoint --ssh-target debian11_test hourly storage/images --test --no-holds --strip-path=1 --keep-source=2 --keep-target=2 --min-change=0 --snapshot-format=autosnap_%Y-%m-%d_%H:%M:%S_daily --buffer 128M --utc
zfs-autobackup v3.2 - (c)2022 E.H.Eefting ([email protected])

NOTE: TEST MODE - SIMULATING WITHOUT MAKING ANY CHANGES

Selecting dataset property : autobackup:hourly
Snapshot format : autosnap_%Y-%m-%d_%H:%M:%S_daily
Timezone : UTC

Source settings

[Source] Keep the last 2 snapshots.

Selecting

[Source] storage/102: Selected
[Source] storage/103: Selected
[Source] storage/104: Selected

Snapshotting

[Source] Creating snapshots autosnap_2024-01-15_10:22:31_daily in pool storage

Target settings

[Target] SSH to: debian11_test
[Target] Keep the last 2 snapshots.
[Target] Receive datasets under: storage/images

Synchronising

[Source] zfs send buffer : 128M
[Target] zfs recv buffer : 128M
[Source] storage/102: sending to storage/images/102
[Source] storage/102@autosnap_2024-01-14_11:08:03_daily: Destroying
[Source] storage/102@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/102@autosnap_2024-01-14_11:08:03_daily: Destroying
[Target] storage/images/102@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/102@autosnap_2024-01-15_10:22:31_daily: receiving incremental
[Source] storage/103: sending to storage/images/103
[Source] storage/103@autosnap_2024-01-14_11:08:03_daily: Destroying
[Source] storage/103@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/103@autosnap_2024-01-14_11:08:03_daily: Destroying
[Target] storage/images/103@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/103@autosnap_2024-01-15_10:22:31_daily: receiving incremental
[Source] storage/104: sending to storage/images/104
[Source] storage/104@autosnap_2024-01-14_11:08:03_daily: Destroying
[Source] storage/104@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/104@autosnap_2024-01-14_11:08:03_daily: Destroying
[Target] storage/images/104@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/104@autosnap_2024-01-15_10:22:31_daily: receiving incremental

Analysing missing 2/2

All tests successful.

`
Without --test

`
(backup) root@debian12:~# zfs-autobackup -v --clear-mountpoint --ssh-target debian11_test hourly storage/images --no-holds --strip-path=1 --keep-source=2 --keep-target=2 --min-change=0 --snapshot-format=autosnap_%Y-%m-%d_%H:%M:%S_daily --buffer 128M --utc
zfs-autobackup v3.2 - (c)2022 E.H.Eefting ([email protected])

Selecting dataset property : autobackup:hourly
Snapshot format : autosnap_%Y-%m-%d_%H:%M:%S_daily
Timezone : UTC

Source settings

[Source] Keep the last 2 snapshots.

Selecting

[Source] storage/102: Selected
[Source] storage/103: Selected
[Source] storage/104: Selected

Snapshotting

[Source] Creating snapshots autosnap_2024-01-15_10:24:34_daily in pool storage

Target settings

[Target] SSH to: debian11_test
[Target] Keep the last 2 snapshots.
[Target] Receive datasets under: storage/images

Synchronising

[Source] zfs send buffer : 128M
[Target] zfs recv buffer : 128M
[Source] storage/102: sending to storage/images/102
[Source] storage/102@autosnap_2024-01-14_11:08:03_daily: Destroying
[Source] storage/102@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/102@autosnap_2024-01-14_11:08:03_daily: Destroying
[Target] storage/images/102@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/102@autosnap_2024-01-15_10:24:34_daily: receiving incremental
[Source] storage/103: sending to storage/images/103
[Source] storage/103@autosnap_2024-01-14_11:08:03_daily: Destroying
[Source] storage/103@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/103@autosnap_2024-01-14_11:08:03_daily: Destroying
[Target] storage/images/103@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/103@autosnap_2024-01-15_10:24:34_daily: receiving incremental
[Source] storage/104: sending to storage/images/104
[Source] storage/104@autosnap_2024-01-14_11:08:03_daily: Destroying
[Source] storage/104@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/104@autosnap_2024-01-14_11:08:03_daily: Destroying
[Target] storage/images/104@autosnap_2024-01-14_11:15:37_daily: Destroying
[Target] storage/images/104@autosnap_2024-01-15_10:24:34_daily: receiving incremental

Analysing missing 2/2

All operations completed successfully

`

[psy0rz]

Yes this is exactly the intended behaviour.

It will thin out all the snapshots in the target path that match the snapshot-format. It doesnt look at properties.

[gpetrom]

Maybe you consider fixing this, a lot of errors could happen and if the target is local that is ok but if you push it in an offsite server that could cause problems.
One more example that could cause a lot of problems.
I have two servers proxmox A and proxmox B
i have in proxmox A vms 100,101,102 running in storage/proxmoxA
i have in proxmox B vms 200,201,202 running in storage/proxmoxB
and i want to backup Proxmox A to Proxmox B and vice versa.
If i forgot to make In Proxmox A the storage storage/proxmoxB false and just enable the backup storage/proxmoxA.
zfs-autobackup will delete source snapshots in Proxmox B.

I know that this is extreme scenario but it could happen

[psy0rz]

there is nothing to fix, since it aint broken :)

just use the correct thinning schema so it wont thin stuff you want to keep.

if you need two different thinning schemas, either use a different target path for each server, or use a different backup name.