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Posted: Tue May 30, 2006 1:34 pm Post subject: Hard Drive Options

In the next month or so, I'm planning on dropping some cash on some new hard drives. My ultimate goal would be 1TB in raid 5, which should last me, well... forever, but this might be a little out of my price range (~$500).

Another option would be mirroring two gigantic disks, obviously less space, and higher cost per GB, but without the need to drop cash on a raid 5 card, the power savings of running 4 drives (two 80GB mirrored, two huge drives mirrored) instead of 6 (two 80GB mirrored, 4 big drives in raid 5).

most of the data on the gigantor array will be ripped CDs and DVDs, which will be replaceable (by re-ripping them from the original media), but i was also planning on using them for incremental backups of things which aren't on the array (/etc, /home, /Users, etc), so it needs to be fairly reliable. Any suggestions?

Posted: Wed May 31, 2006 5:41 am Post subject:

I think that a raid 5 might be a little overkill to store things that can be 're-ripped' from the original media; not to mention the controller is likely to cost more that a couple bucks. It would probably be much more economical to do a raid 1 of similar capacity (economical in terms of overall price, system complexity, power usage and heat dissapation). Less space per dollar, but probably still more economical than then a raid 5 when you take the controller into account.

Also, please keep in mind that although the raid1/raid5 array is redundant, it is still not a substitute for real backup. If the data being backed up is important to you it should be placed on removable media or an external drive.

The price you are figuring on I take to be SATA (~500 is a bit low for SCSI)...

Guide Dog Joined: 08 Nov 2003 Posts: 8402 Location: MN

crewsr wrote:
Also, please keep in mind that although the raid1/raid5 array is redundant, it is still not a substitute for real backup. If the data being backed up is important to you it should be placed on removable media or an external drive.

Yeah because your still going into a raid card that can fail. and then your sunc unless you can get the same kinda card again to get the information off.

(reason number 1 why I went with software raid, Reason 2 was big drives, and I wanted part stripped and part mirrored... can't do that with hardware raid)

honestly, I'd say spend the money right now (but then I also just got paid...) and save your self the worries later.

Posted: Wed May 31, 2006 7:34 am Post subject:

after looking into it a little more, software raid using LVM or ZFS is looking very promising. how processor intensive is software raid? if i reinstall the OS, is it easy to remount the software raid array?

Posted: Thu Jun 01, 2006 6:08 am Post subject:

I suppose it would depend on the OS, but as an example I have been running a simple OS-managed stripe set on an XP box, that when it was time to nuke the OS and reinstall, the OS recognized the set and and assigned a drive letter with no interaction necessary on my part.

Stripe sets and mirrors require negligible processing overhead. A raid 5 set probably would require a bit more, since the parity has to be computed.

Guide Dog Joined: 08 Nov 2003 Posts: 8402 Location: MN

I have 4 partitions on my linux box: swap, boot, root, storage.

swap is stripped, boot and root are mirrored, and storage (mostly for video capture) is striped.

after 2 days of uptime the total amount of CPU time used by all of the raids comes to less then a minute... (most of that at boot time for verifying the arrays; athlon XP 2500 mobile, down clocked to 2200 because my motherboard sucks)

windows raid I've moved a pair of mirrored drives to a new machine, after a bit of work with the permissions on the NTFS file system it was ready to roll.