Question : keep older backups than sanoid snapshots

[loxK]

Hello,

Sorry it is more a question than an issue ...

I have this config :

[vm]
    use_template = ssd
    recursive = yes
    process_children_only = no

[backup/BACKUP]
    use_template = backup
    recursive = yes

[template_ssd]
    frequently = 12
    hourly = 24
    daily = 4
    monthly = 0
    yearly = 0
    autosnap = yes
    autoprune = yes
    capacity_warn = 80
    capacity_crit = 95

[template_backup]
    frequently = 12
    hourly = 24
    daily = 30
    monthly = 6
    yearly = 0
    autosnap = no
    autoprune = yes
    hourly_warn = 2880
    hourly_crit = 3600
    daily_warn = 48
    daily_crit = 60

I backup this way :

/usr/sbin/syncoid --recursive --no-sync-snap --preserve-recordsize vm backup/BACKUP/vm

After a while syncoid fails complaining that snapshots of the origin datasets are missing. What is the proper syncoid command to keep older snapshots than what is available in origin dataset ?

[jimsalterjrs]

After a while syncoid fails complaining that snapshots of the origin datasets are missing. What is the proper syncoid command to keep older snapshots than what is available in origin dataset ?

Stop using --no-sync-snap, that's literally what it's for. To give you a snapshot to base incrementals on which won't be removed.

If you want to use --no-sync-snap, then it's on you to make sure that you are keeping an eye on things and making sure you replicate frequently enough that your newest snapshot on the target doesn't become older than the oldest snapshot on your source.

And since your custom "ssd" template takes no monthly snapshots, your monthly=6 on the target has no effect. Can't preserve six monthlies if you never get any monthlies in the first place. Set monthly=1 on your source, if you want the target to be able to build up a cache of monthlies.