Currently, we have no way of seeing options set to md(4) devices. Fix: https://github.com/freebsd/freebsd-src/pull/1210 # mdconfig -a -f /root/backup.iso -o readonly -o verify Before: # mdconfig -l -v md0 vnode 1536K /root/backup.iso After: # mdconfig -l -v md0 vnode 1536K /root/backup.iso - readonly,verify