Greetings, I've been using this gimmick for backing up some OpenBSD 7.6 systems: https://github.com/thexhr/openbsd-timemachine For the purposes of this discussion, it:
1. uses hotplugd to run a script when you plug in a USB backup drive 2. this script mounts the backup drive 3. it then uses rsnapshot (rsync basically) to back up the data 4. the script unmounts the backup drive Everything is just fine until step 4, when the backup drive refuses to unmount. If you try to do it yourself, you see: umount: /my_backup_mount_point: Device busy This doesn't seem to be a temporary issue: after an hour's wait, the drive still can't be unmounted. I'm not sure how to debug the problem since fstat shows no open file on the drive, nor any process using any directory on the drive as a working directory. Also, fuser -c shows no usage of the drive. Restarting or turning off hotplugd doesn't free up the drive for unmounting either. Is there some other reason why the drive would remain in use that I could investigate? Thanks for any suggestions, --T
