How to remove a drive from a 2-drive RAID 5 array?

Posted by DrSAR on Super User See other posts from Super User or by DrSAR
Published on 2011-11-28T17:53:23Z Indexed on 2011/11/28 18:10 UTC
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raid

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mdadm

There is some information available on shape changes in RAID arrays but I'm a little nervous and would like confirmation:

Problem: I have 2 500GB drive as software raid 5 (mdadm). I would like to free one of the two drives since RAID-redundancy is for wimps... Can I just

mdadm --grow --array-size=1

followed by a

mdadm --grow --raid-disks 1?

This seems too simple. How would I specify which drive gets freed? Part of the reason for this maneuver is that I don't have additional space to run a backup.

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