Questions about RAID!

[QTPie]

I have RAID 66 (highpoint chipset) and 2 80GB UDMA 100 HDDs.
I want to use them in RAID 1 (mirroring) setup.
Since I've never set up a RAID system b4, I need your advice.

I have 1.2GB Thunderbird, 768MB RAM, GF2 GTS, U2W SCSI card with 9.1GB HDD as C drive (NTSF) loaded with WINXP.

1.
In reality, how much is RAID 100 faster than RAID 66? Is it worth it for me to buy a RAID100 card?

2.
If I change the controller or move these HDDs to a difference PC later, will my data still there?

3
Can I format them in NTSF and run Diskeeper defragmentations?

 

[Wuzup101]

1. I'm not really sure as I've only run raid arrays on 100's. However I would guess for a raid1 setup they would be the same difference as normal 66 and 100 drives, as a mirroring setup isn't any faster than normal drives to my knowledge. If you want speed, Raid0 is where it's at.

2. I've always wondered this, and from most of my research, and from people saying different things about there experiences in the forums, I'm guessing no. However, I have never tried it. I think switching controlers and possibly raid chip sets would require a clean reinstall of everything on the drive. Though I could be wrong. I really don't want to try to press my luck with my drives

3. Yes. They run just like normal HDD's. Format and defrag them as you would any normal hard drive (as the computer will only see them as 1 HDD).

 

[RazeOrc]

Might want to do a search on RAID threads, there are tons...

 

[QTPie]

Wuzup101 -- Thank you for your very helpful info.
RazeOrc -- Thanks. I already did that, but most ppl have their RAID array in mode 0 for speed.

I don't care much about speed, just the safety of my data. Since I have about 40GB of data, I don't like to put them on CDs (as you might say).

I still don't have the answer to question 2. If anyone has done it before, please share your experience. Thanks

 

[BatmanNate]

Take into consideration that RAID-1 is no faster than a single drive, if anything (especially with IDE) it is going to be a slightly slower configuration, just because your system has to calculate the mirroring. Granted this isn't a large calculation like it would be for RAID 3 or 5, however it should result in an ever so slight speed decrease, probably not noticable on that system. Given this, the difference between ATA100 and 66, which is normally only around 3% with a single drive, should be negligable as well. (Throughtput shouldn't be a huge issue again) Moving the array from one system to another is feasible assuming that you keep the drives in the SAME CONFIGURATION, ie connected to the same channels on the same settings. The configuration information should be stored in the boot tables of the HD's, and the RAID controller should be able to regonize it assuming everything is in the same place. As far as how the system views the drive (from the OS perspective) it is the same as a single drive. Formatting, defraging, etc. all are the same. Good luck!

 

[QTPie]

BatmanNate - Thank you very much for your info. I think I'll use my RAID 66 card.

The RAID-1 array is non-bootable. It's used for storage only.
Currently, I use it in my PC (Iwill KK-266 MB, TBird 1.2G, 9.1 GB U2W SCSI bootable with WINXP, drive C.)

About moving the RAID-1 array without losing data, the scenarios should be something like this:

1.
For some unexpectable reasons, my PC can't boot; I have to format drive C and reinstall OS (either WIN2k or XP)

2.
Upgrade system to dual CPU and/or change to another RAID card (probably a hardware RAID)

It is said that I can't change the RAID controller without rebuilding the disk mirror image (i.e. all data will be lost, which is not what I want).
I'm also thinking about not using RAID-1 but a backup software instead. I'll use 2 HDDs as 2 separate drives and setup the software to sync them (Iomaga QuikSync for example)
What is your opinions? I appreciate your help.

 

[BatmanNate]

If your boot drive were to crash, it would not present any sort of problem to the array in question, the boot drive could simply be replaced and the data on the array would remain intact. As for switching controllers, it is possible that the data could be kept, but unless the controllers used the same or a very similiar chipset, I highly doubt that it would function. (Not 100% sure on this) Upgrading to a hardware raid card for a raid 1 configuration is almost moot, due to the relatively low CPU usage of raid 1 in the first place. The only reason I could forsee justifying a hardware raid card would be the need to upgrade to raid 5 or another proccessing intensive raid mode that requires parity calculations. (or SCSI for that matter) Software should do you just fine if IDE raid 1 is all you have in mind. (Particularly with dual CPU's) However, if it is still a concern, ghosting the drive for backup purposes would also be an option, however it would not offer you the same level of fault tolerance due to the span of time between backups. My 2¢...

 

[QTPie]

According to Highpoint Chipset specs, you can move from 66 RAID to 100 RAID for their Highpoint chipsets.
Backup data on CDs using Ghost is very inconvenience due to time consuming and data integrity when you have a large amount of data (10+ GB)

Anyway, I think I'll set up RAID-1 array. Thank you very much for your help!

 

[PH0ENIX]

Well I must admit I dont know too much about IDE RAID, but in SCSI the array config is stored on the non-volitile SRAM on the array controller.

Because of this, switching to another controller means re-configuring the array.
There may be implementations of RAID that store the array config on the drives themselves, but it would have to be striped like parity data, otherwise what do you do if the drive with your config dies?

I'd highly doubt your drives would be able to max out the throughput of an ATA66 channel.
So i'd say the difference there would be negligible.

You can format in NTFS, but I dont know if diskeeper supports it.
The seagate tools I have do, but WD I could only guess. (why? cuz I wouldnt buy WD, but thats my 2c)

Oh and, I would have though RAID1 was reasonably I/O intensive, being that all disk instructions have to be executed in tandem.
I did see benchmarks of this sort a while ago in the forums, but I forget what the results were.
Because of that, (again just my opinion) I'd say a hardware RAID controller would make a decent difference to system load.

Good Luck!

 

[QTPie]

Thank you very much for your info!