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Using POE to power PI, how to check for power loss

Wed Jan 03, 2018 8:12 pm

I have a Raspberry PI 3 that has over multiple PI's and SD cards been corrupting the SD cards. I believe this is a result of power loss from Power over Ethernet. I have the same configuration in other locations that have not experienced this issue. I was wondering if anyone knew how to check to see if the PI is losing power randomly throughout the day. I know when a Windows machine is shut off unexpectedly that is boots up and shows a warning about the recent shut down. Does the PI have any sort of notice like this? Is there something in the logs that would indicate a sudden loss of power? Any information would be greatly appreciated!

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Re: Using POE to power PI, how to check for power loss

Thu Jan 04, 2018 3:59 pm

At the moment of loss of power, the Pi will not have time to write anything to a log. You will only see entries from when the power comes back and the unit boots.

The command "uptime" will tell you how long it was since last boot.
The command "journalctl --list-boots" will give you a list of boots that is in the system logs.
( If the last command says that there are no journal files, try with "sudo" and/or create the folder "/var/log/journal" )

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