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On Wed, 2005-08-31 at 21:46 -0600, scotthathcock@×××××××.net wrote: |
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> Is there a good Howto on migrating from a non Raid disk to Raid? I |
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> recall seeing one but can't find it now. |
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|
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If you're really lazy (like me), you can convert your current running |
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system over to RAID without messing with reinstalling from backups |
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(although you probably should make the backups, hopefully you won't have |
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to use them). Assuming you're doing RAID1, get your partitions and such |
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set up on your new drive. Then set up the raid array (the howto on |
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tldp.org is helpful, although be sure to use the newer mdadm setup even |
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though the docs are a little thinner in the howto) on your new drive, |
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marking the other drive in the array as bad/down. Copy say, /dev/hdxy |
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to /dev/mdx, and then edit the proper config files so that when you |
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reboot you'll be using the raid array. Once you're in it, change the |
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other drive in the array from bad to the old drive, and it'll rebuild |
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the array on the fly. It's pretty neat. |
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|
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(If you do that method though, read the docs very carefully to make sure |
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you're doing it right. It's been a while since I've done it so I may |
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have gotten something backwards or some such.) |
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|
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I wouldn't worry about any performance hits: A few months ago I |
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converted an old P2 450mhz system to RAID 1+0 and noticed no performance |
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hits, and even went to raid1 + lvm and again no problems. I've since |
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added an additional CPU to that box, but hard drives are just so much |
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slower than your CPU that it'd take a lot of work to create a slowdown. |
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|
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Also, if there's any chance you'll want to maybe resize your partitions, |
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or especially, add more drives to the system, I would very strongly |
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suggest looking into LVM (Linux Volume Manager). It plays well with |
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raid (instead of raid1+0 I'm doing the equivalent with raid1+lvm, but no |
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worries about adding more disks) and lets you alter "partitions" on the |
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fly. If you want to add more storage, just buy a pair of drives, raid1 |
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them, then just append it to the end of your volume, and run your |
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favorite on the fly partition resizer and enjoy. |
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|
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By the way, a $15 promise ATA100 two channel IDE PCI card + a pair of |
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$80 120gb seagate HDDs is quite a nice deal. I've got two of the |
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Promise IDE cards in my server, and they seem to be pretty good PATA |
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cards if you're into that sort of thing. |
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|
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Kyle |
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-- |
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