Hi.
CENTOS 7.6.1810, fresh install - use this as a base to create/upgrade new/old machines.
I was trying to setup two disks as a RAID1 array, using these lines
mdadm --create --verbose /dev/md0 --level=0 --raid-devices=2 /dev/sdb1 /dev/sdc1 mdadm --create --verbose /dev/md1 --level=0 --raid-devices=2 /dev/sdb2 /dev/sdc2 mdadm --create --verbose /dev/md2 --level=0 --raid-devices=2 /dev/sdb3 /dev/sdc3
then I did a lsblk and realized that I used --level=0 instead of --level=1 (spelling mistake) The SIZE was reported double as I created a striped set by mistake, yet I wanted the mirrored.
Here starts my problem, I cannot get rid of the /dev/mdX no matter what I do (try to do).
I tried to delete the MDX, I removed the disks by failing them, then removing each array md0, md1 and md2. I also did
dd if=/dev/zero of=/dev/sdX bs=512 seek=$(($(blockdev --getsz /dev/sdX)-1024)) count=1024 dd if=/dev/zero of=/dev/sdX bs=512 count=1024 mdadm --zero-superblock /dev/sdX
Then I wiped each partition of the drives using fdisk.
Now every time I start fdisk to setup a new set of partitions I see in /var/log/messages as soon as I hit "W" in fdisk:
Feb 25 15:38:32 webber systemd: Started Timer to wait for more drives before activating degraded array md2.. Feb 25 15:38:32 webber systemd: Started Timer to wait for more drives before activating degraded array md1.. Feb 25 15:38:32 webber systemd: Started Timer to wait for more drives before activating degraded array md0.. Feb 25 15:38:32 webber kernel: md/raid1:md0: active with 1 out of 2 mirrors Feb 25 15:38:32 webber kernel: md0: detected capacity change from 0 to 5363466240 Feb 25 15:39:02 webber systemd: Created slice system-mdadm\x2dlast\x2dresort.slice. Feb 25 15:39:02 webber systemd: Starting Activate md array md1 even though degraded... Feb 25 15:39:02 webber systemd: Starting Activate md array md2 even though degraded... Feb 25 15:39:02 webber kernel: md/raid1:md1: active with 0 out of 2 mirrors Feb 25 15:39:02 webber kernel: md1: failed to create bitmap (-5) Feb 25 15:39:02 webber mdadm: mdadm: failed to start array /dev/md/1: Input/output error Feb 25 15:39:02 webber systemd: mdadm-last-resort@md1.service: main process exited, code=exited, status=1/FAILURE
I check /proc/mdstat and sure enough, there it is trying to assemble an Array I DID NOT TOLD IT TO DO.
I do NOT WANT this to happen, it creates the same "SHIT" (the incorrect array) over and over again (systemd frustration). So I tried to delete them again, wiped them again, killed processes, wiped disks.
No matter what I do as soon as I hit the "w" in fdisk systemd tries to assemble the array again without letting me to decide what to do.
Help! Jobst