I am using RH9 and a vp6 mobo running the RAID0 via the mobo hardware with 2 80 gig HDs, everything is running fine. Although I had one question

Should is see both drives combined as one 160 Gig drive?? I had thought it would show as one 80 gig drive instead as 1 160 gig drive? How could i have 160 gig of stoarge if the data is being stripes to each drive?

Zack

For RAID 0, if the file is 4 kilobytes in size. Half of it (2 kilobytes) will be stored on one drive. The other half (2 kilobytes) will be stored on the other drive. If you have 3 hard drives, it will write 1/3 of the file size to each hard drive. Four hard drives will be 1/4 of the file will be written to each hard drive and so on.

RAID 0 or RAID 5 does not work as well for partitioning. Its best to use RAID 0 or RAID 5 as whole.

RAID 5 is RAID 0 + parity. It needs three hard drives.

RAID 1 is mirroring, so you don't get double the size and you don't get increased throughput. The advantage of RAID 1 over RAID 0 is data backup. RAID 0 has no data backup and you will have a higher chance of losing your data.

OK thats good but does it mean i should see 160 gig from 2 drives or should i see 80gig

Also how do i determine what cluster size my drives are right now?

Zack

160GB - like he said files are split so access times are faster, but you'll still have 160GB.

Clusters - what file system are you using?

Usually, if you haven't _specified_ a files system, it'll be in 4K blocks.

OK i see well still but i am confused If RAID stores the same data on both drives, and i store 80 gig of data, then how could i go past 80 gig if the max on one drive IS 80 gig??


Heee confusing huh um yeah i left it default runinng RH9 um files system is 3 or whatever the newest one is i forget the name

RAID 0 doesn't store the same data on each drive. RAID 0 takes _half_ of each file and puts one half on each drive.

Each drive has data that is completely different from the data on the other drive.

So if you have a file that is "ABCDEF", ABC is on drive 1 and DEF is on drive 2.

If the file is, say 15 MB, it's split so 7.5 MB of the file is stored on drive 1 and the other 7.5 MB is stored on drive 2.

Because the RAID is writing to both disks at the same time, you could write an 80GB file to disk and 40GB would be written to drive 1 and the other 40GB would be written to drive 2. This would leave you with 40 GB of space on each disk - 80Gb remaining free space in total.

(sorry if this sounds patronising)

I SEE!!

Damn i didnt read the reply good enough, ok thanx

Now if i wanted to go with MIRROR in case i have a drive failure what would i have to do??

Also does anyone know of any good backup solutions using USB and RH9??

Zack

How many partitions did you make. What is the total space that your data took up. Type df -h at the prompt.

After you got the information, you have to buy a cheap hard drive. Next, at the command prompt login as root and copy the files to the cheap hard drive. Then go into the controller BIOS and delete the raid array. Next make the array as a mirror. Copy the files to the RAID array. You have to change your fstab file for your setup.

Thats half right, but it works by writing ACE on the first drive and on the second drive its writting BDF.

Yeah, you're right - was more concerned with getting 1/2 and 1/2 idea across though.