health-btrfs

Sends a health report

see

• https://superuser.com/questions/789303/how-to-monitor-btrfs-filesystem-raid-for-errors

• https://unix.stackexchange.com/questions/193619/list-all-btrfs-filesystems-and-subvolumes-in-shell

• https://www.freedesktop.org/software/systemd/man/systemd.unit.html