RAID Questions

palmer · Guru Joined: 17 Nov 2004 Posts: 320 Location: Berkeley, CA

I already have a SATA drive (250gb)
I would like to get 3 more and build a 750gb RAID5 (software)
Is it possible to do this without deleting the data on the old drive?

I was thinking something like this:
RAID5 is ok if 1 drive fails (can read/write)
Make a 4-disk RAID5 over 3 disks (degraded)
Transfer the files over the the array
Rebuild the array

Should cost me ~$350
Anybody know of a standalone raid drive (external USB/FireWire) that's cheaper?

2nd off:
What is a good filesystem for a big drive?
I would prefer something that lasts a long time (can be defragmented)
I hear the reiserfs can't be defragmented
So that leaves ext3, XFS or JFS...
(Not trying to start a flame war)

-palmem

Boris27 · Posted: Sat Feb 04, 2006 7:52 am Post subject:

I don't think there are any defragmenters for Linux... The only way to defrag your files is to back them up, empty the disk and put the files back on again.

I think it should be possible to do that without losing data. Maybe you can start with the 3 new disks in a raid, copy the data from the old disk on it and then add the old disk to the raid.

Or something. IANARE (I am not a RAID expert).
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HydroSan · Posted: Sat Feb 04, 2006 7:54 am Post subject:

LINUX FILESYSTEMS DO NOT FRAGMENT.

STOP SPREADING THIS STUPID PROPAGANDA.

THANK YOU.
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feld · Guru Joined: 29 Aug 2004 Posts: 593 Location: WI, USA

LOL ^^^^

From what I've read XFS handles file fragmentation the best. It works excellent with huge filesystems and huge files too.

-Feld
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< bmg505> I think the first line in reiserfsck is

if (random(65535)< 65500) { hose(partition); for (i=0;i<100000000;i++) print_crap(); }

HydroSan · Posted: Sat Feb 04, 2006 8:02 am Post subject:

I was being totally serious.

:|
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Server status: Currently down, being replaced with fresh install - 20% completed.

sn4ip3r · Posted: Sat Feb 04, 2006 3:04 pm Post subject:

Actually, there is a "defragmenter" which uses the filesystem itself to defragment it. Might not be as fancy or fast as a real defragmenter, but should work well enough on all major linux filesystems.