After being out of town for about a week, I came back to find my OMV server non-responsive (login prompt for Web GUI eventually just timed out). I tried omv-firstaid initially, but received the following error:
From there, I decided to try rebooting to see if that made any difference, but of course it did not; in fact it made matters worse (Web GUI just results in a "Bad Gateway" error and none of the services I use are running).
Looking into this error (specifically the last line about no usable temporary directory) lead me to posts suggesting that the disk could be full or permissions could be set to read-only, but I'm not seeing either of those as an issue in my case. Below are a few things I've checked to see if anything stood out, but I'm out of ideas. Hoping someone might be able to give me some next things to try to get back up and running.
Here's the output of "df -h" showing that nothing (save one of my backup data drives) is close to full:
Here's an "ls -ls" showing permissions should allow for write access for /tmp and /var/tmp (I don't have a /usr/tmp):
When I try to create a file in /root, I get an error, but when I try to create a file in /home I do not, despite both being on the same physical device and both showing as having available space: