Hello, I managed to find the raid6check utility here: https://salsa.debian.org/debian/mdadm I downloaded and compiled the code, ran mdadm --stop on my array, and ran ./test . Many of the tests failed, but more concerning is that I cannot restart my array. # mdadm --verbose --assemble /dev/md0 mdadm: looking for devices for /dev/md0 mdadm: /dev/sda has wrong uuid. mdadm: No super block found on /dev/sdb (Expected magic a92b4efc, got 00000000) mdadm: no RAID superblock on /dev/sdb mdadm: No super block found on /dev/sdc (Expected magic a92b4efc, got 00000000) mdadm: no RAID superblock on /dev/sdc mdadm: No super block found on /dev/sdd (Expected magic a92b4efc, got 00000000) mdadm: no RAID superblock on /dev/sdd mdadm: No super block found on /dev/sde (Expected magic a92b4efc, got 00000000) mdadm: no RAID superblock on /dev/sde What do I do now? If the test utility is so dangerous, why is there no warning to pull your HDDs before you run ./test? Like, make test normally doesn't bork anything. Thanks!