Comment 1 for bug 1891586

This log line is particularly interesting:

2020-08-14 05:47:44 ERROR juju.service.systemd service.go:127 failed to list services for application "juju-db": List failed (/bin/systemctl list-unit-files --no-legend --no-page -l -t service | grep -o -P '^\w[\S]*(?=\.service)'): error executing "/bin/systemctl": Failed to list unit files: Connection timed out;

Is this on a focal machine by the way? If so, can you also check journalctl output for any auth-related errors raised by systemd. I've seen errors like this with nested lxd containers running focal (in those case, the culprit seems to be apparmor).