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Further Adventures with Software RAID

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I have now commissioned our new file server. The two disks reporting reallocated sectors have stabilised and there has been no change to the number for ten days. My research (a quote from the Seagate support forums) indicated that there are a lot (maybe even thousands) of spare sectors on the 1.5TB drives so I decided to go ahead and commission the new file server after adding a sixth disk (a Samsung 1.5TB) to take the space to 7TB. Using my own blog post to add and grow the raid worked fine after I fixed the "mdadm --grow" example to include the "-n 6" parameter. Without that the extra disk was kept as a spare disk !

There is one other thing to do - use "tunefs" to remove the reserved space that Linux automatically keeps on each disk. For a storage medium why keep 5% or more unused?

See http://www.walkernews.net/2007/02/28/tune2fs-increase-linux-free-disk-space/ for more details on how to do this and why you might want to.

I will wait a few weeks before reusing the old 1TB drives just in case.

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