number_of_disks=4 chunksize_in_kib=512 chunksize_in_b=$[chunksize_in_kib*1024] array_data_size_in_kib=$[chunksize_in_kib*(number_of_disks-2)*number_of_disks] array_data_size_in_b=$[array_data_size_in_kib*1024] devs="$dev1 $dev2 $dev3 $dev4" # default 2048 sectors data_offset_in_kib=$[2048/2] layouts="ls rs la ra parity-first ddf-zero-restart ddf-N-restart ddf-N-continue \ left-asymmetric-6 right-asymmetric-6 left-symmetric-6 \ right-symmetric-6 parity-first-6" for layout in $layouts do for failure in "$dev3 3 3 2" "$dev3 3 2 3" "$dev3 3 2 1" "$dev3 3 2 0" \ "$dev4 3 3 0" "$dev4 3 3 1" "$dev4 3 3 2" \ "$dev1 3 0 1" "$dev1 3 0 2" "$dev1 3 0 3" \ "$dev2 3 1 0" "$dev2 3 1 2" "$dev2 3 1 3" ; do failure_split=( $failure ) device_with_error=${failure_split[0]} stripe_with_error=${failure_split[1]} repair_params="$stripe_with_error ${failure_split[2]} ${failure_split[3]}" start_of_errors_in_kib=$[data_offset_in_kib+chunksize_in_kib*stripe_with_error] # make a raid5 from a file dd if=/dev/urandom of=/tmp/RandFile bs=1024 count=$array_data_size_in_kib mdadm -CR $md0 -l6 --layout=$layout -n$number_of_disks -c $chunksize_in_kib $devs dd if=/tmp/RandFile of=$md0 bs=1024 count=$array_data_size_in_kib blockdev --flushbufs $md0; sync check wait blockdev --flushbufs $devs; sync echo 3 > /proc/sys/vm/drop_caches cmp -s -n $array_data_size_in_b $md0 /tmp/RandFile || { echo sanity cmp failed ; exit 2; } dd if=/dev/urandom of=$device_with_error bs=1024 count=$chunksize_in_kib seek=$start_of_errors_in_kib blockdev --flushbufs $device_with_error; sync echo 3 > /proc/sys/vm/drop_caches $dir/raid6check $md0 0 0 2>&1 | grep -qs "Error" || { echo should detect errors; exit 2; } $dir/raid6check $md0 repair $repair_params > /dev/null || { echo repair failed; exit 2; } blockdev --flushbufs $md0 $devs; sync echo 3 > /proc/sys/vm/drop_caches $dir/raid6check $md0 0 0 2>&1 | grep -qs "Error" && { echo errors detected; exit 2; } cmp -s -n $array_data_size_in_b $md0 /tmp/RandFile || { echo cmp failed ; exit 2; } mdadm -S $md0 udevadm settle sync echo 3 > /proc/sys/vm/drop_caches done done