63 lines
1.1 KiB
Markdown
63 lines
1.1 KiB
Markdown
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---
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tags:
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- Linux
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- procedural
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- systemd
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---
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# Timed `systemd` units
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In order to use [systemd](./systemd.md) in the manner of [cron](./Cron.md) (but
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with added benefits, such as being able to set the user to run as, environment
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variables and so on), you first create a timer template, e.g.:
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```
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# everyhour@.timer
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[Unit]
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Description=Run %i every hour
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[Timer]
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OnCalendar=*-*-* *:00:00
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Persistent=true
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Unit=%i.service
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[Install]
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WantedBy=timers.target
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```
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You can then pass in specific units using this template to `systemctl`.
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As an example, this unit runs a simple bash script that pings a server:
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```
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# ping-eolas-api.service
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[Unit]
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Description=Ping Eolas API to check it is up
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[Service]
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User=thomas
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Group=thomas
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Type=oneshot
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ExecStart=/home/thomas/self-host/scripts/ping_eolas-api.sh
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```
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Then when enabling the service, do the usual:
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```sh
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systemctl daemon-reload
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```
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But when enabling/starting, invoke the timer template, viz:
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```sh
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systemctl enable everyhour@ping-eolas-api.timer
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systemctl start everyhour@ping-eolas-api.timer
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```
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The schema is:
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```
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[timer_template_name][service_name].template
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```
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