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On Tuesday, August 14, 2018 10:52:30 PM CEST John Covici wrote: |
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> On Tue, 14 Aug 2018 16:06:21 -0400, |
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> |
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> J. Roeleveld wrote: |
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> > On August 14, 2018 11:42:18 AM UTC, John Covici <covici@××××××××××.com> |
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wrote: |
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> > >I use sanoid/syncoid to back up using zfs. Its great, keeps snapshots |
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> > >for as long as I want them (I use 80 days for now). And it keeps |
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> > >hourlies for the last couple of days as well, so I could roll back in |
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> > >case of a problem. Very nice if you use zfs. |
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> > |
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> > I tried sanoid, but it has a few problems which really become annoying |
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> > when you have a lot of datasets: 1) every dataset is handled seperately, |
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> > no use of recursive snapshots when datasets are inside the same tree 2) |
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> > it keeps seperate hourly, daily,.... snapshots, which means it will |
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> > happily create multiple snapshots with only a few seconds difference for |
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> > every dataset around midnight. 3) when rolling back several snapshots, |
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> > there are multiple errors reported because the cache (where does it store |
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> > that?) does not match reality. |
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> > |
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> > Have these been resolved yet? |
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> > |
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> > I ended up writing my own system for this, got some extra intelligence in |
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> > there to work around any possible error condition I have encountered. |
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> Well, I got around your second point by having a special job at 11:59 |
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> pm to create the dailies and the one at midnight works well. I only |
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> do the cron jobs hourly, not every minute like they wanted. |
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> |
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> If your script is not special for you, I would like to see it, maybe I |
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> would use it instead. Things seem to work for now, however with those |
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> modifications. |
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Current code is too specific for my situation. I think you would be quicker to |
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write something yourself instead of modifying my code. |
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The steps are: |
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- Check if an snapshot needs to be done (incl. type: hourly, daily, weekly, |
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monthly) |
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- If yes: |
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1) create a recursive snapshot on the entire pool |
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2) remove unnecessary snapshots (temp, swap, |
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placeholders,not_for_current_type) |
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3) register snapshots into database |
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4) clean up old snapshots |
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Because I register actual snapshots and point snapshot-type entries to these, |
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I can quickly determine which snapshots are really unecessary. This also |
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drastically reduces the amount of snapshots on the system. (My SAN currently |
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has 2611 ZFS snapshots). |
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I also found it is far quicker to create a recursive snapshot on the entire |
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pool and then removing all the unecessarily created ones. |
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-- |
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