mirror of https://github.com/schoebel/mars
37 lines
1.4 KiB
SYSTEMD
37 lines
1.4 KiB
SYSTEMD
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[Unit]
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Description=MARS per-resource trigger from /mars/resource-@{res}/systemd-trigger
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Documentation=https://github.com/schoebel/mars/docu/mars-manual.pdf
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## Prohibit parallelism with any daemon-reload
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After=daemon-reload.service
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## The per-resource trigger is the _only_ one which is allowed
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## to remotely start / stop any units dealing with resources.
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## Otherwise, races or conflicting start / stop operations might
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## occur, leading to deadlocks / failures / etc.
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##
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## General rule: each *.path watcher can only start its corresponding
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## *-trigger.service at most _once_ in parallel (provided that the actions
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## caused by "marsadm systemd-trigger-extern" are not forking into background).
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## So there is never any parallelism of _any_ unit with exactly _itself_
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## (although _different_ units are allowed to run in parallel to each other,
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## of course).
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## Do not start both the global and any of the per-resource triggers
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## in parallel.
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## It could lead to various races between global and per-resource units.
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## In contrast, different per-resource triggers are not mutually exclusive.
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After=mars-trigger.service
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[Service]
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# Important for blocking parallelism with itself
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Type=oneshot
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RemainAfterExit=no
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# Important for avoiding failures: do not send any signals
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KillMode=none
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# Important: the resource argument will keep remote triggers disjoint
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ExecStart=/usr/bin/marsadm systemd-trigger-extern @{res}
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[Install]
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WantedBy=mars.service
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