I have a systemd service that I install via debian package using the apt command on a raspberry pi 4. I've been using journalctl -xef to keep track of all log output for debugging purposes while installing the package and running the service.
I'm not sure how I managed this, but at some point today, apt's log output as well as the output of my package's maintainer scripts stopped showing up in the journal. I did have several typos in one of my package's maintainer scripts and I have a tendency to fat finger the keyboard or press the hotkeys sometimes, but I can't find anything in particular that might've caused the issue. It seems that the journal defaults to in-memory storage as well, which is a bummer, because the first thing I tried to fix the issue was a reboot. So now I guess I can't even look back at old journal entries to see if there was something in there that might indicate what had happened.
I also thought perhaps some of the changes I'd made today in the service or package were causing the problem, so I tried installing an older proof-of-concept service/package and that too does not write correctly to the journal.
I've tried to find a way to just reinstall or repair the apt/apt-get/dpkg installation, but haven't been very successful. Most questions are related to repairing a package installation using apt, not repairing the installation of apt itself. I also tried to see if there was a way to configure where apt writes its logs, but most questions along those lines are related to redirecting stdout/stderr when running an apt command.
I'm very new to linux and all of the technologies listed above, so I'm not sure how to debug/diagnose this further.
Is there a way to repair/restore the apt/apt-get/dpkg installations or configurations on a raspberry pi or is my only option to try to restore to factory defaults or re-install the entire OS?
Update
Today I learned of the /var/log directory. I haven't found any indication within those logs of what caused this issue, but it does appear that the the problem also extends to syslog, messages, user.log and daemon.log (i.e. output from apt/apt-get and from package maintainer scripts is missing from these as well). I can see several apt install/upgrade/purge operations successfully logged in those files and then no more. I can tell there should be more entries logged, however, because my package calls systemctl daemon-reload and I can see systemd[1]: Reloading in the logs. From browsing /var/log/dpkg.log, it seems that none of those entries were every shown in journald, so that seems to still be fine. Logs from /var/log/apt/term.log are definitely missing from journald, but logs from /var/log/auth.log are still present.
