hard-drives - Page 2

Oerdin · January 3, 2003, 02:48

MtG is on a thread closing rampage. Quick some body humor him before he closes this one!

Ted Striker · January 3, 2003, 03:05

Well, for mid range needs, the ATA100s and ATA133's are pretty good, though I have personally seen some reliability problems. Maybe we just got a bad batch?

I wouldn't skimp on the hot swap bays though in the enterprise, they make life so much easier and prevent bloody knuckles.

Urban Ranger · January 3, 2003, 03:30

Bloody knuckles? That's what chainmail gaunlets are for.

MichaeltheGreat · January 3, 2003, 03:30

Quote:

Originally posted by Oerdin
MtG is on a thread closing rampage. Quick some body humor him before he closes this one!

Just letting people know I'm around, is all.

Graag · January 3, 2003, 04:04

I'm in the market for a new HDD at the moment...
my plan was to also go for the WD 80GB (good choice Jon

), but all this talk of RAID has befuddled me...

My main use for the HDD will be video editing and rendering, so I want the fastest possible HDD (for the money), though it'd be very nice to not have to worry about HDD failure when editing important video.

If I buy the WD 80GB HDD now, could I then buy another in a few months and a RAID card? Is a motherboard with onboard RAID in any way preferable?
Will RAID mean slower data tranfer rates?

Help!

I'm also debating which motherboard to buy, but thats for a different thread... *opens boring motherboard thread*.

Ted Striker · January 3, 2003, 04:14

Hi Gragg,

I will let the hardware pros answer specifics. But in general:

You should usually buy the drive and the RAID cards at the same time. RAIDs need a minimum of 2 drives if you are using mirroring (RAID1).

If you want the fastest possible drives out there, you should get a SCSI drive. These carry a big price tag with them though, but they are blazing fast.

There shouldn't be much difference between a built in motherboard RAID card and a seperate RAID card.

The single drive system has worked well for most people, as long as you are diligent in backing up your important work. In my case, I have been too lazy sometimes to make sure I have backups, so I like to have something that is automatic, which is the beauty of a RAID1.

So it depends on your user habits. As Edan said, if you are confident that you will back up your files as you need to (like you burn them onto a CD on regular basis) RAID might be overkill. But is a definite luxury to have and can make life much easier.

alva · January 3, 2003, 04:18

ATM go with that one, best value for money.

MichaeltheGreat · January 3, 2003, 04:19

If you're talking real time, high res video editing, Seagate makes (or used to, they may not bother now that Ultra320 SCSI is available) a line of 10k and 15k RPM SCSI drives that are optimized for video work.

SCSI is not THAT expensive, once you digest the controller, and if you run Win2k, you can do a software RAID5, rather than having a RAID adapter.

You want to go to NTFS anyway for that sort of work.

Graag · January 3, 2003, 04:20

Thanks for the help Ted... I'm afraid SCSI is a bit out of my range!

I still don't quite see how RAID works... in what sense is my data safe if one of the 80GB HDD fails? If both drives are full of data, how can RAID stop me losing it?

Oh, and the other point I should add is that I would still intend to run my current Seagate 20GB HDD with my OS, the 80GB HDD(s) would be purely to store video intended for editing. Would RAID still work in this case?

Graag · January 3, 2003, 04:22

Thanks MtG....

But I am on a very limited budget, SCSI isn't an option. I'm lucky to able to afford the new CPU which will make the HDD necessary in the first place

Software RAID sounds promising, but I'm still not sure I see the point of RAID at all

alva · January 3, 2003, 04:23

Because the data is on both drives...

Ted Striker · January 3, 2003, 04:31

Well, to keep it simple, I'll use RAID1 as the example. In a RAID1, you have two drives, in a "mirror" mode. So, basically, the two hard drives are exact copies of each other. Say you have a gragg.mpg file, and you save it to your hard drive. In RAID1, that file is going to be saved on both drives instantaneously.

Okay, say you have your RAID1 up and running. Your primary drive fails!

Normally you would be screwed at this point, your system would shut down, and you would lose all your data. But with a RAID1, it will automatically switch to the backup drive, which is an exact copy of the primary drive. Your system will continue to run without interrption, and all data is saved.

When you're done working, and you shut down your pc, at that point all you have to do is pull the bad drive out and replace it with a new drive. Then you generally tell the RAID card to rebuild this new drive by copying the secondary drive onto the (new) primary drive.

Some RAID cards are so hard core that you don't have to do anything. You just slap a new drive in there and it will know how to rebuild the new drive. Almost always you will be able to work while the new drive is building also.

For your second question, technically there are some RAIDs you can build with different sized drives, but generally you want the drives to all be the same size, so I would say in your case, no, you won't be able to use a RAID.

What I do sometimes when I have two drives is to save important files on both drives, but again, that relies on your diligence.

Graag · January 3, 2003, 04:40

Ok I think I get it... the data is split across both drives, they kind of act as one.
If I should have understood this by now ignore the question... but if you've got you're two 80GB RAID HDDs pretty full, e.g. 140GB of data and one fails, how can the other store enough data to provide a mirror of the first?

Ted Striker · January 3, 2003, 04:50

Well, in a RAID1, the drives are actually mirrored.

So, if you have two 80GB drives in a RAID1, you will only be able to hold up to 80GB.

Graag · January 3, 2003, 05:05

Oh. That simple huh? Think I'd rather have two 80GB drives then. All seems like a bit of a waste of space to me, unless the data was real vital.

Ted Striker · January 3, 2003, 05:07

Yeah that's the tradeoff you have when you use a RAID1. You lose half of the space but you get data protection.

There is another RAID called RAID5 where you actually can combine the space and get data protection, but you need 3 drives and that's probably overkill for a desktop.

Graag · January 3, 2003, 05:11

I actually have 3 20GB HDDs at the moment, but only run two as I don't have the space for the third!

But RAID 5 is an intriuing option. Or at least would be if I had a lot more money lying around.

I'm just happy I can finally do a bit of video editing

OneFootInTheGrave · January 3, 2003, 08:50

Huh,, I wish that I could buy a 200GB hard drive, with all the downloads of the net and movies etc... my 80 GB hdd (the same as yours is already 45 GB full after only three months when I reformatted the last time

+games and similar. Can't believe this is happening to me

.. that I want an even bigger HDD. At least this 80 GB is kind of a minimum that still is OK. 40 GB would clearly be to little.

I will have to clean it though and burn all the stuff on CD's as an alternative even though it is neater when you have it all on HDD. (takes less time to burn for friends or play, etc... if it sits on HDD).

I think I will wait until the HDD manufacturers start producing HDDD's with 80 GB per platter and 160 GB drives will cost under 100 £. That will be the time for another one.

Edan · January 3, 2003, 10:33

Quote:

Originally posted by Graag
But RAID 5 is an intriuing option.

In case anyone is interested, here's how raid 0 and 5 work.

In raid 0, the data is striped across 2 or more disks of the same size. Which means that the 2 or more disks are seen as one giant disk 3 times the size of one disk, and the data, when written, gets written accross all three disks, with the first part of the data getting written on the first disk, the next part on the second disk, and so on, until youve finished all the disks and returned to the first disk. It's like having a book written accross 2 or more books, where the first letter in the book is in the first book, the second is in the second book, and so on. This offers no backup protection (indeed, if any single disk dies, *all* the information on all the disks is gone - which means there's a greater chance of failure, since you now have more disks that can potentially fail), but it does allow for bigger partitions (ie, you could buy 3 80gb drives and have a 240 gb single partition, which would be much cheaper than buying a single drive thats 240 gb ) and it also can offer some performance increase (since it's writing to 2 or more disks, it can write quicker since, to some extent, they can be writing at the same time in effect. Although you don't get a 2x speed increase, I don't think).

Raid 5 works simmilar to Raid 0, with 3 or more disks striped. The last disk in the raid, however, is a parity disk, that writes duplicate information (which means the performance increase isn't as much as Raid 0, but there's still some). If one of the drives were to fail, the raid software would be able to use the parity disk to compute what the information in the dead drive was - although that means a potentially big preformance loss. If you were to lose 2 disks, though, you would lose all the information - although it's rare that 2 disks would go at the same time.

Raid 10 and 50 are combinations of the various raid schemes. There are a few more raid schemes that are rarely, if ever, used.

Edan · January 3, 2003, 10:47

Quote:

Originally posted by Ted Striker Okay, say you have your RAID1 up and running. Your primary drive fails!

Normally you would be screwed at this point, your system would shut down, and you would lose all your data. But with a RAID1, it will automatically switch to the backup drive, which is an exact copy of the primary drive. Your system will continue to run without interrption, and all data is saved.

Something else to point out - this only works if it's a hardware problem. If it were software-related or user mistake (ie, you deleted your registry or your windows directory or data that you wanted a backup of

), the same mistake would be duplicated on your second drive

Ted Striker · January 3, 2003, 19:26

Correct.

alva · January 3, 2003, 21:08

Since there many HD specialists here, I gonna jump in ask a question too
I recently bought a new MOBO
aopenAK-77 8X max
http://www.aopen.nl/products/mb/AK77-8XMax.htm

I have 3 ide channels on the MOBO, but only two of them show up in both BIOS and Windows (XP),
WHY???
AFAIK this MOBO does not have a RAID function..
so do I need special software/drivers or something?

Ted Striker · January 3, 2003, 21:31

I can't get the image on their webpage to show up and it doesn't show up here either.

Could that third slot be a floppy connector?

OR

It only shows two controllers:

Integrated ATA133 Controller
Promise ATA133 and Serial ATA Control Chip

The second one handles 2 kinds of connections but I thought the serial ATA connector doesn't look like normal ATA connector?

alva · January 3, 2003, 22:04

not a floppy,
the serial connector is located higher up.

I'm pretty sure it's an IDE channel, the cables fit

hmm, don't pictures show up?
Could you try this one?
http://club.aopen.com.tw/pss/largevi...ak77-8xmax.swf

it's a flash image

Ted Striker · January 3, 2003, 22:22

Okay I see it now. That's a pretty cool magnifying glass feature on that flash.

My guess is that those two slots on the right are connected to the same controller? Which controller is connected to those two slots? Once we know that we can probably do some more investigation.

I'm sure you checked this, but in your BIOS settings is there a switch to turn on the other slot?

alva · January 4, 2003, 00:54

There is
channel 0 (yellow right down)
channel 1 (yellow right up * 0&1 could be the other way around, but I don't think so)
and surprisingly channel 2

(yellow left)

the first two each can have a master and slave combo (normal stuff )
the third one AFAIK doesn't do anything..
I checked my BIOS thouroughly(sp?) and nothing indicated anything like that.
Maybe I should check it again, it's quite awhile since I've done so.

It is a cool use of flash isn't :cool

Could this whole thing have anything to do with 'striping'?? hmm, that is a term used alongside RAID isn't it?

Urban Ranger · January 4, 2003, 00:55

Quote:

Originally posted by Ted Striker
The single drive system has worked well for most people, as long as you are diligent in backing up your important work. In my case, I have been too lazy sometimes to make sure I have backups, so I like to have something that is automatic, which is the beauty of a RAID1.

You could have a tape drive and an archival program (say, CA Arcserve) running in the background that is scheduled to do incremental backups. All you need is to remember to rotate the tapes.

Of course, this is going to be more expensive than an IDE RAID.

Urban Ranger · January 4, 2003, 00:59

Quote:

Originally posted by Edan
Something else to point out - this only works if it's a hardware problem. If it were software-related or user mistake (ie, you deleted your registry or your windows directory or data that you wanted a backup of

), the same mistake would be duplicated on your second drive

That's why enterprise systems have tape backups in additional to RAID drives.

Ted Striker · January 4, 2003, 01:00

Quote:

Originally posted by alva
There is
channel 0 (yellow right down)
channel 1 (yellow right up * 0&1 could be the other way around, but I don't think so)
and surprisingly channel 2

(yellow left)

the first two each can have a master and slave combo (normal stuff )
the third one AFAIK doesn't do anything..
I checked my BIOS thouroughly(sp?) and nothing indicated anything like that.
Maybe I should check it again, it's quite awhile since I've done so.

It is a cool use of flash isn't :cool

Could this whole thing have anything to do with 'striping'?? hmm, that is a term used alongside RAID isn't it?

It is certainly possible that the two on the right are for a RAID, though I don't see any mention of RAID on your motherboard specs anywhere.

I know Promise is the most popular maker of onboard RAID chips for the desktop.

Urban Ranger · January 4, 2003, 01:04

IIRC, the Promise chip is an IDE RAID controller. Check your BIOS for RAID options.

Edit: Nevermind, Promise makes a whole range of controllers. Can you list the model number of the controller chip?