It`s bare metal install root on zfs raid10, uefi boot, asrock e3c236d2i intel pentium G4560T 16G ecc-ram. Second test/backup/home server on consumer j4205 mb.
I started 1putty whith "dmesg -wT" another with "journalctl -f" and reproduced the problem (zpool scrub rpool in web shell) server hang...