Rebuild mdadm RAID5 array with fewer disks

Posted by drjeep on Server Fault See other posts from Server Fault or by drjeep
Published on 2013-08-02T15:26:41Z Indexed on 2013/08/02 15:41 UTC
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linux

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raid

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mdadm

I have a 4 disk RAID5 array, one of which is starting to fail according to smartd. However, since I'm using less than half the space on /dev/md0, I'd like to rebuild the array without the failing disk.

The closest scenario I've been able to find online has been this post, however it contains bits that don't apply to me (LVM volumes) and also doesn't explain how I go about resizing the partition after I'm done.

Please note I have backups of important data, but I'd like to avoid rebuilding the array from scratch if possible.

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