Questions about RAID

[thecoolnessrune]

Hey guys, I'm looking to begin a RAID setup but I have questions.

First of all, I have two IDE disks. One is 160GB, the other is 120GB. I want to mirror the OS boot drive. If I create a 120GB partition on the 160GB drive, can I use the two drives in a RAID 1 array as an OS boot?

Second of all, I want a RAID 5 array for storage (starting with 3 1.5GB HDDs).

Can you run a RAID 1 card and a RAID 5 card in the same system? If I went all SATA, could I run a RAID 1 and a RAID 5 array off the same card?

Lastly, what happens if a card dies? Is your data still there? Can you install a new card and access your data? Do you have to stay with the same brand or model? With RAID 1 do I just unplug one of the drives and still be able to use either as the boot drive till the card is replaced?

Thank you all for some answers.

 

[mooseracing]

First of all, I have two IDE disks. One is 160GB, the other is 120GB. I want to mirror the OS boot drive. If I create a 120GB partition on the 160GB drive, can I use the two drives in a RAID 1 array as an OS boot?

Most you won't even need to partition, the RAID hardware will take care of it, the extra space won't be usable.

Can you run a RAID 1 card and a RAID 5 card in the same system? If I went all SATA, could I run a RAID 1 and a RAID 5 array off the same card?

Depending on the how much data you run it all off of one card as the card handles multple version of RAID. I doubt you have enough data to be saturating both or data that needs to be moved a few seconds faster by having seperate cards. But yes it is doable.

Lastly, what happens if a card dies? Is your data still there? Can you install a new card and access your data? Do you have to stay with the same brand or model? With RAID 1 do I just unplug one of the drives and still be able to use either as the boot drive till the card is replaced?

Card dies, data is still on the drives. Get a card of the same time and import your foreign array. The card has to be same model and revision for the highest chance.

You never know what will happen though, that is why backups are important.

Yes with RAID 1 you can unplug a drive and use the other while still connected to a card. IF you take the RAID card out of the picture, it's basically like disconnecting your mobo, now what can you do?

 

[thecoolnessrune]

Soo even though RAID 5 and RAID 1 is for backup, as soon as I lose a card, I'm screwed unless I can happen to find a card of the same type?

Kinda takes the wind out of my sails to do RAID. Seems to make more sense just to do an autobackup with external drives..

So its either I buy twice as much HDD space as I need.. or I buy two expensive RAID cards... Doesn't seem worth it in either aspect

 

[mooseracing]

RAID is meant for aleiving spindle failure and increased performance.

For home use RAID is worthless, IT IS NOT A BACKUP. Although it's funny to see the post on here for people that treat it that way.

 

[RebateMonger]

Originally posted by: thecoolnessrune
So its either I buy twice as much HDD space as I need.. or I buy two expensive RAID cards... Doesn't seem worth it in either aspect

If your data is important, then you need a backup somewhere. Don't trust a single hard drive or a single array with valuable data. As mooseracing notes, RAID (1, 5, 10, 50, etc.) is not "backup". It's a way to help with uptime. It's far from 100% reliable (some would argue it's LESS reliable than non-RAID) and I've definitely seen businesses lose extremely valuable data on RAID arrays.

 

[BonzaiDuck]

Originally posted by: RebateMonger

Originally posted by: thecoolnessrune
So its either I buy twice as much HDD space as I need.. or I buy two expensive RAID cards... Doesn't seem worth it in either aspect

If your data is important, then you need a backup somewhere. Don't trust a single hard drive or a single array with valuable data. As mooseracing notes, RAID (1, 5, 10, 50, etc.) is not "backup". It's a way to help with uptime. It's far from 100% reliable (some would argue it's LESS reliable than non-RAID) and I've definitely seen businesses lose extremely valuable data on RAID arrays.

I've got some four RAID0's running here at home -- for a few years. But another I installed on a machine at my brother's house failed. I keep looking over my shoulder thinking that somebody fooled with the BIOS setup for the hardware controller I'd installed. But you expect that sort of thing from RAID0, so you back up on a regular basis.

I have a RAID5 on one system that I backup regularly to a RAID5 on a LAN file-server, which in turn gets backed up regularly to a hot-swap auxiliary IDE drive. I have two or three of the latter, and play round-robin with them.

[Just to share my thinking, I worry that when I die, all the stuff I've written, software projects, textbook drafts, e-mails etc. -- could be lost to posterity. So I'm obsessive about "backing up." My great work must live on after me . . . . ]