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Reviving to say I moved one of my boxes to timers after this thread and then moved it back when I realised I'd forgotten how to read the journal on a read-only rescue boot. journalctl -D /mnt/var/log/journal for next time.

That was it. Cron started in my home directory, so ./readings.db was a brand new empty database. Absolute paths and a cd at the top of the script. Marking resolved.

Use absolute paths for the database and output file. Also redirect stderr to a log so you can see if sqlite is opening a different database.

Trying to dump a small sqlite database from cron. Running the script in a terminal works, but the nightly output is a zero-byte file. The crontab line is: 15 2 * * * /home/me/bin/export-readings.sh The script uses ./readings.db. Does cron s…

On points perhaps. My timers are still running.

I'll take it. Thread closed, I win.

OnFailure= pointing to a unit that sends a mail. You have to write that unit. I'll give you that one, cron wins on this.

Fine. One real point: cron mails me on failure and it's built in. What do you do with a timer?

user timers need loginctl enable-linger or they stop when you log out. that one cost me a week of missing backups

Cron's environment has caught me more than anything else on this list. PATH with nothing in it, wrong cwd. A service unit can have the same issue but at least you can test it with systemctl start and get the same environment as the real run…

The log file can.

For the record here's what the whole thing actually is: # backup.service [Service] Type=oneshot ExecStart=/usr/local/bin/backup.sh # backup.timer [Timer] OnCalendar=--* 02:15:00 Persistent=true RandomizedDelaySec=300 [Install] WantedBy=time…

Timers still need a service file, a timer file and a daemon-reload to do what one line did. I'm with sysv. Grudgingly, since I don't agree with him about anything else.

No. I found out about flock when four rsyncs were running at once.

And you remember it every time? Honest question.

flock -n /tmp/x.lock cmd. Eleven characters plus a filename.

The other one for me is overlap. A timer won't start the service again while it's still running. With cron a slow job stacks up unless you remember to wrap it in flock.

So install anacron.

I had the same view until a sensor box was off for a night and missed its backup. Persistent=true runs the missed job at next boot. With cron you need anacron for that.

Every six months somebody tells me to move my jobs to timers. So: two files instead of one line, and a unit name I now have to think of, so that I can read the output through journalctl instead of a plain file. What exactly do I get? I've b…