To summarize, there are two issues:
1. snaps were not mounted on restart for some reason
2. this lead to loosing all auto-connected interfaces on snapd start (because snap.yaml files couldn't be read from disk)
The cause of problem #1 is unknown and we had a couple of reports about this in the past. Snaps are automatically mounted by systemd mount units on boot, so why this didn't work is unclear.
To summarize, there are two issues:
1. snaps were not mounted on restart for some reason
2. this lead to loosing all auto-connected interfaces on snapd start (because snap.yaml files couldn't be read from disk)
The cause of problem #1 is unknown and we had a couple of reports about this in the past. Snaps are automatically mounted by systemd mount units on boot, so why this didn't work is unclear.
For problem #2 I've proposed a fix here: https:/ /github. com/snapcore/ snapd/pull/ 10814 and with it connections should be preserved on such failures.