Reassign drive index number of mdadm software raid devices

us flag

My RAID 1 array has two disks as stated by # mdadm --detail /dev/md0

    Number   Major   Minor   RaidDevice State
       5       8       32        0      active sync   /dev/sdc
       4       8       16        1      active sync   /dev/sdb

Somehow mdadm assigned /dev/sdc on raid device index 0 and /dev/sdb on raid device index 1

Is it possible to reassign driver so /dev/sdb gets raid device index 0 and /dev/sdb raid device index 1?

za flag

No and that's absolutely pointless.

First of all, this is impossible. Drives are scanned asynchronously, what is sda now can become sdb after a reboot. On some hardware when you build a kernel without this feature you can have more controlled ordering, but no guarantees even in that case.

Then, why bother at all? Don't stare to those numbers. They are internals, they aren't meant for you. They only have some limited interest for those who do forensics or data recovery, but not for you; you should do proper backups rather that relying on black magic for data recovery.

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