08:18:51 <szilard> Hi. I am trying to create and delete ZFS snapshots using the crontab, creation works ok, but I am facing issues with the deleting part.
08:19:00 <szilard> The crontab entry looks like this:
08:19:11 <szilard> SHELL=/usr/bin/zsh
08:20:15 <szilard> 10 21 * * * /usr/sbin/zfs destroy -r tank@`TZ=$TZ+167 date +'%Y-%m-%d'` 2>> /var/log/zfs.destroy
08:20:27 <szilard> However I am getting the following error:
08:20:53 <szilard> zsh:1: unmatched `
08:22:18 <szilard> If you are wondering the +167 is the maximum offset value TZ accepts, with this I attempt to delete snapshots older than 7 days, or so.
08:23:18 <szilard> the command works just fine in root ZSH shell, but it fails in crontab, so there must be some differences, but I don't know, how to find it.
08:25:06 <szilard> I have already tried to change the command to : tank@$(TZ=$TZ+167 date +'%Y-%m-%d') but it didn't help
08:25:29 <szilard> Please let me know if oyu have any better solution for this.
08:59:06 <tomww> your could move the code into a shell script file with #!/usr/bin/zsh on the first line and led crontab call that file
09:07:26 <tomww> my apporach to deleting autmatic snapshots is having a dedidacted constant part in the name like "autobackup_" and the date in seconds. Then a zfs list -r -t snapshot -o name | grep autobackup_  and then not delete the last n-number snapshots
09:08:16 <tomww> (or egrep "@autobackup_1[0-9]*$" )
09:12:21 <szilard> tomww: Thanks for the hint, I'll test it and will also think about your approach.
09:12:24 <szilard> Thanks again.
09:23:26 <tomww> you’re welcome
09:57:27 <szilard> I'd liek to use a USB drive for cold backup. I'd liek to have a ZFS pool on it, so i can send snapshots there. Am I supposed to create a partition and create Zpool on that partition, or should I use the raw device itself for the pool?
10:54:22 <szilard> tomww: what do you think about this aproach:
10:54:24 <szilard> /usr/sbin/zfs list -d 1 -H -o name -t  snapshot | grep "tank@" | tail -n +7 | xargs /usr/sbin/zfs destroy -r
10:55:20 <szilard> -d 1 means it lists non-recursively (so it emmits only the top level dataset names
10:55:39 <szilard> -H means it ommits the output header (this is not really needed)
10:55:56 <szilard> -o will instruct zfs to list only the name property
10:56:22 <szilard> tail -n +7 means it ommits the first 7 items
10:56:41 <szilard> So it deletes all snapshots except the 7 most recent ones
11:43:02 <tomww> I try to never stript a "destroy -r". instead I try to identify every single zfs filesystem and loop over that one to find all snapshots in there.
11:45:52 <tomww> and for the first run I prefix the destroy command with "echo" to only see the command it _would_ run.
11:50:34 <szilard> tomw, I agree.
11:50:44 <szilard> I have modified my script like this:
11:51:08 <szilard> /usr/sbin/zfs list -d 1 -o name -t snapshot | grep "tank@autobackup"     | tail -n +7 | xargs /usr/sbin/zfs destroy -r
11:51:47 <tomww> note: I'm only reading occationally here, so scripting support is very limited on my side
11:51:49 <szilard> included autobackup in the grep, so it will list only applicable snapshots from tank and will keep the 7 most recent version
11:52:32 <tomww> I still do not use a "-r" in destroy. think of a clone dependent on a snapshot. I might be killed the clone.
11:55:00 <szilard> I haven't tried zfs cloning feature yet.
11:55:13 <szilard> I haven't used many of the zfs features yet.
11:55:20 <szilard> But thanks for the hint.
15:16:07 <oninoshiko> if a clone is dependent on a snapshot -r is not enough to delete it. You need -R in that case.
16:47:46 <szilard> I am wondering, why is there . and .. in my /
20:16:21 <tux0r> . is everywhere
20:20:09 <jayjwa> . and .. show up in my omnios and linux systems in /