raid and hard dirve...

[insanity]

ok i jux bought a fairly new motherboard that has a promise raid controller....

i want to setup 2 harddrives to act as one, so it will be double the speed for read/write...(that wut i think it can do with raid, not sure)

anyway do i hav to buy 2 identical hardrives, i mean same amount of gig, RPM, and access time......
???

thank you

[emunoodle]

It doesn't have to be the same size or speed. But your RAID will run at the speed of your slower drive. Also the size will be double of the smallest drive (depending on the type of RAID your setting up, I'm assuming RAID 0). IMHO they(the drives) should have the same specs to get the most out of the configuration.

[The Whizzard]

I'm not sure about IDE but for SCSI, the best way to do it is to get exactly the same drives except for the batch. Getting drives from the same batch can cause problems with the controller accessing the correct drive because the latency is too close to each other.

Also, with only two drives, your best bet for increased performance is to mirror the drives. Striping would give you capacity but with a performance hit.
If I were you, I'd get 4 drives with RAID 5 for absolute best performance and maximum capacity.

IMHO, IDE RAID should have never been invented. The IDE bus was never meant for this type of application.

[thread_killer]

Actually, for speed, striping without parity is the way to go. You get no fault tolerance though. For maximum redundancy striping with parity. To simply create on large virtual drive (Raid 0) you don't need the same size drives, and it's actually pretty easy to set up. The linux documentation project has an excellent HOWTO on configuring all kinds of RAID setups.

[andycrofts]

..try the Redhat 8.0 documentation, called (something like)
System Administrator Primer.

Worth printing out, in any case. Damn good (not geek'y) advice/info.
-Andy

[xsystemx]

hello,I am running linux on a 233 with 2GB HD. Couple people I know are each going to give me an HD "around 2GB" give or take.

I was wondering what Raid would be best so linux would reconginze it as a 6GB partition. I am not worried about performance nor the speed. I just want to make it so its 6GB

[mdwatts]

http://www.murty.net/ataraid/ should help.

[insanity]

ok i jux found out that my raid controller only support raid 0 an 1

all i want is faster read/write so raid 1 is out..

last choice raid 0, is the speed gonna be fast?? is it worth the time and money to setup raid 0? i might use this system for a webserver so i need fast read/write

[thread_killer]

Raid 0 is just making one logical drive out of the two drives you already have. ie...instead of two ten gig drives, the computer is going to act as though you have one twenty gig drive. No appreciable hardware performance increase, just more space. Raid 1 is nice because if you have a massive head crash on your drive, you still have all your data on the other drive. I just set Raid 1 up on a box, and it works great. On most of my servers I use RAID 1 for the operating system, and RAID 5 for all the data.

[mdwatts]

Originally posted by thread_killer
Raid 0 is just making one logical drive out of the two drives you already have. ie...instead of two ten gig drives, the computer is going to act as though you have one twenty gig drive. No appreciable hardware performance increase, just more space. Raid 1 is nice because if you have a massive head crash on your drive, you still have all your data on the other drive. I just set Raid 1 up on a box, and it works great. On most of my servers I use RAID 1 for the operating system, and RAID 5 for all the data.

Actually you will gain quite a performance increase if you using Raid0 (striping).

http://www.linuxjournal.com/article.php?sid=2359

[thread_killer]

I shall eat my hat.....I was confused. RAID 0 is is striping without parity. My mistake. I've never made an array that wasn't fault tolerant.....what's the point?

:o

[mdwatts]

Enjoy your hat. I hear ketchup goes well with them. :D

The point? Well not everyone can afford scsi raid controller and drives and the IDE raid included on motherboards is a cheap alternative though of course not as good.