mdadm auto grow raid

Posted by johannes on Server Fault See other posts from Server Fault or by johannes
Published on 2010-03-16T20:24:02Z Indexed on 2010/03/16 20:31 UTC
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Filed under:

raid

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linux

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mdadm

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growth

I have a raid0/1 on lvm logical volumes. I resized the logical volumes. Now I want to resize the raid to use the complete logical volumes. This can be done with

mdadm /dev/md? --grow -z newsize

But somehow I can't figure out how to calculate the newsize argument. Is there a way to tell mdadm to grow to the biggest possible size? If not, how do I calculate the biggest possible size of the raid to use for the newsize argument?

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