SATA or IDE Hard Drives?

[Thomas 0]

Say, I am reviewing the need to have Raid 5 for my CCTV systems. I think it may be an overkill. An overkill which costs much more. I am thinking perhaps that as and when one of the hdd fails, I will downgrade it to a Raid 1.

 

Anyone with any thoughts on this? Rory??

 

Raid 1 isn't a downgrade from 5. Raid 1 is mirroring which takes your drives and has half of them be an exact copy of the other half. If you have four drives in Raid 1 then two drives worth of space will show up. With Raid 5 and four drives, three would show up and the fourth acts as backup.

[Soundy 1]

With Raid 5 and four drives, three would show up and the fourth acts as backup.

 

Not exactly... RAID 4 dedicates one disk to backup "parity" data; RAID 5 uses the same amount of parity data (one disk's worth) but stripes it across all the drives in the array. This way, any one disk can fail, and the array can still be rebuilt.

 

http://en.wikipedia.org/wiki/RAID_5#RAID_5

[chewingyu 0]

So, from the sound of you guys' views, looks like Raid 5 is not that 'bad' after all, eh?

 

 

 

 

BTW, to all who responded, I meant no disrespect to u guys by calling out to Rory. Thanks for your responses

[Soundy 1]

It's not "bad" - it's actually a good thing (RAID 6 is even better, by that token, because it uses dual-parity and you can suffer TWO failed disks without data loss). Whether it's the RIGHT thing, FOR YOU, is the only question. For most people it's not worth the added cost, but if your data integrity is important...

 

Used to also be a question of whether it was worth the complexity to set it up, but new systems like I linked to above make it downright simple. Cost of disk space also used to be a big factor, given the "loss" of one disk's worth of space for parity, but disk space is so cheap these days (1TB drives for $200, 1.5TB drives on the way), that's not really a factor anymore either. If you're storing that much data, what's an extra 10-20% to ensure it's safe?

[chewingyu 0]

I guess you have a point there, Soundy. Thanks.

Will have to mull over it...

[Soundy 1]

BTW, there are cheaper ways to do it... RAID controller card for your machine (most onboard controllers only do RAID 0 and 1), or a smaller/cheaper external array (Enhance makes four-channel units as well), and they certainly don't have to all be 1TB drives. I just linked to the R8S as an example - it's a beautiful system, but in itself is probably overkill for most people. RAID 5 itself, though, isn't.