[Nut-upsuser] UPS shuts down on NUT boot with low battery [APC Back-UPS RS 550G]

Charles Lepple clepple at gmail.com
Tue Jun 11 14:52:26 BST 2019

On Jun 11, 2019, at 1:37 AM, Marc Finns wrote:
> Thanks for the reply. However these two FAQ are unfortunately not describing the situation. 
> - The first issue is that NUT switches off the UPS upon reboot on low battery (not that it dies because of low battery)
> - The second issue is that the UPS does not recognise being online again (not that the PC does not restart)

My apologies, I misinterpreted "UPS does not return to AC mode" as the UPS AC output, and did not carefully read the first issue.

However, I still maintain that there are a few features missing from this class of UPS (or they are mapped to proprietary APC HID usages). It is possible that the Synology shutdown strategy is using a different command.

With the devices powered from something other than the UPS under test, can you grab a log from something like "/lib/nut/usbhid-ups -DDD -a ups -k 2>&1 | tee /tmp/APC_Back-UPS_RS_550G_shutdown.txt"? The usbhid-ups driver selects one of several shutdown commands, and I think we will need at least 3x -D to see that logic in the debug output. Please gzip the log before emailing

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