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My Server shutsdown . Evertime at midnight.

The acpi Event power_button is triggered. at /etc/acpi/events/power_button

# care about the power button

How can i find out the "Caller" or the Trigger of this event ?

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power_button is a script, so all you need is to save executing backtrace from that script. The idea is to write a script that analyzes processes tree from launched power_button upwards and the caller process should be somewhere within.

See this answer. Put the script into /usr/lib/acpid/power_button and save its output to a file: that should identify the offender unless the reason is not a data-center's cleaner guy :)

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Depends exactly on your flavour of linux, but I've found this helpful in the past:


Also using "lastcomm" to find the preceding processes.

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