Anyone tried this before?

[circumflatulator]

Hello. First "forum" post ever. Medium PC savvy. Retired hardware/software engineer.

Built rack-mount P4-3GHz Intel-mobo machine with XP-Pro 1 year ago to hold my CD collection. Ripped over 300 music CDs in .wav format onto 1 250GB HD. Worried about drive crash, so added another 250GB and copied all files for manual backup. Worked great.

Since then have got into video. Bought more drives and ripped some of my DVDs. Started recording off satellite too. That computer is now just a file server for the other computers that actually play the media around the house. Now over 2TB but no backup for video stuff if HD fails.

Much google research made me decide to go RAID-5.

Researched RAID controllers. My mobo only has PCI slots but all the large capacity (6 SATA ports and above) RAID boards require PCI-X.

Ran into hack http://www.tomshardware.com/storage/20041119/ to activate RAID5 in XP. Sounds great. But I can't seem to find answers to the following nagging questions:

1. Is ANYONE actually using this hack? Does it work good? I don’t care too much about write speed, but needs to read at least as fast as the individual drives/volumes do now. Is it reliable?

2. How many 250GB drives is the max this hack will allow?

3. Does it have a GB or number-of-drives limit to a single large RAID-5 volume?

4. Are there any negative aspects to very large RAID5 volumes using this hack?

5. Since I’d like to keep adding drives to the RAID-5 volume(s) as my library grows, can that be done easily? Or does the array need to be created to its maximum size before copying any files to it?

The answers to all these questions are available for the hardware RAID controllers, but can’t find diddlysquat about that XP hack.

Since the risk of losing all my data is great if there were to be a problem adding drives later on, I’m really can’t move ahead until more is learned.

Any feedback would be appreciated. Thank you!

[TheBlackMan]

I have not done this or even heard about it before; however after doing a quick Google for "xp raid hack" I was brought to this link. Hopefully it provides you answers to your questions.

[circumflatulator]

Thanks BlackMan. It took about 30 minutes to check out every part of that site but it was worth it. I think I'll have to email some of the folks in that sites guestbook who have tried the RAID-5 setup to get some real-world feedback, as the benchmarks and comments in the rest of the site only seemed to refer to RAID-0 and RAID-1.

Thanks again.

p.s. I would have sworn I googled every site on the internet with "XP RAID-5" in the searchbar. How this one escaped my search is a real mystery.

[jaclaz]

Not to put you down or anything, but wouldn't be an option to use a dedicated system?

Just an idea, bu this is really cheap (less than the price for XP):

http://www.rebyte.com/content/view/122/25/

Also, keep an eye on this:

NASLITE

http://www.serverelements.com/

RAID support is expected in next releases

jaclaz

[circumflatulator]

Thank you for the ideas, jaclaz And don’t worry about hurting my feelings: I know enough to know I know very little about this stuff! (what a weird sentence)

Checked out the reByte hardware – but it has two limitations my present setup doesn’t have: 1- Only 4 drives are supported. 2- Only IDE drives supported. Since I already have nine 250GB drives in my machine and need more space, the 4-drive limitation is a killer. Also, I learned early on that having a bunch of IDE drives in one box made cable layout a nightmare. So the last 4 hard drives are all SATA and they are a joy to work with. The reByte seems to be a good answer if it wasn’t for those limitations.

The NASLite product is also limited to a maximum of 4 drives. And they also indicate the drives must be IDE. However this product seems to be targeted at using multiple computers, each with up to 4 IDE drives, all networked together to create a NAS server farm. I guess that is an option if my hopes of keeping all the drives inside one large fileserver turns out to be an unworkable idea.

I realize that these limitations may be overcome in these companies’ next releases, but I am out of disk space now and need to do something soon. That’s why the XP hack looked so appealing to me. Quick and cheap. Just wish I could find out what its limitations are.

Again, thanks for the links. All ideas and options welcome!

[jaclaz]

Yes, of course the "real" solution would be a farm of SCSI drives, but prices are way too expensive.

Cheers,

jaclaz

[kurt476]

Serial ATA is much faster then IDE, EIDE, SCSI. Serial ATA go's upto 1.50 MBs per sec or more, that's all i know

Edited July 30, 2005 by kurt476

[shaggy8675]

Hy there, and thank you for visiting my Raid Site.

The reason there are no raid 5 benchmarks posted on there, is that i don't run raid 5 myself, and i have not recieved anny benchmarks from raid 5 from visitors.

I do have some pictures of raid 5 arrays using Softwar-Raid.

Check them:

But i have to say these are duall athlon SCSI systems using PCI-X, so the bandwith is much higher than either ATA or S-ATA ( max 150MB/sec ( round 120Mb/sec in real life )

It does work, and it's a cheap way for creating safe large storage, instead of buying expensive Hardware Raid cards, wich also can't go over the 150Mb.sec bandwith of normal Mainboards. ( different storry for PCI-X 133 capable boards! )

But the new S-ATA2 with 300Mb/sec and PCI-Express are looking to be the future.

SCSI is great but uindeed expensive, but disks like the WD Raptors are great, also the 16MB AX 10 HDD etc.

When using them on a good S-ATA2 Mainboard, this should ( in theory ) work wonders.

Time will tell.

As for the limitations...well as far as i know, there are little.

It's just how manny disks you can adress thru your setup manager. As you see in the SCSI pic above 6 is no problem ( all on 1 scsi U320 cable )

That all depends on how your machine has been built/setup, ata/s-ata controller wise.

4. Are there any negative aspects to very large RAID5 volumes using this hack?

Yes, the setup is slow...verry slow. it needs to create the disk array wich might take hours. And in case of hdd failure, the newly added hdd will also be slow to get setup again. but it will work.

Manny people talk about proccesor usage, but with the modern procc, at speeds of 2 to 3 ghz or more what is 3 to 7% Procc usage?

No problem at all.

Hope this helps a little.

Shaggy,

www.software-raid.tk

Edited July 30, 2005 by shaggy8675

[spidercop]

why not use use bigger drive or use hot swap drive like this u can u use on hot swap system fore the backup en the other drives internal

http://www.granitedigital.com/catalog/pg47...ivessystems.htm

http://www.firewire-1394.com/hot-swap-firewire-kit-1077.htm

wen using same size drives hot swa^p is best option for backup in my mind

[shaggy8675]

why not use use bigger drive or use hot swap drive like this u can u use on hot swap system fore the backup en the other drives internal

http://www.granitedigital.com/catalog/pg47...ivessystems.htm

http://www.firewire-1394.com/hot-swap-firewire-kit-1077.htm

wen using same size drives hot swa^p is best option for backup in my mind

<{POST_SNAPBACK}>

But than he would have 9 useless hdd hehe. If he was to buy bigger or all external disks...would cost more money.

[jcarle]

What you need is something like the 3ware 8000 Series Serial ATA Raid Controller cards.

When the challenge is to increase storage capacity while controlling costs, one Serial ATA (SATA) RAID controller family gives IT professionals what they need to accomplish both goals - the 3ware 8000 Series RAID controllers from 3ware. With the ability to support up to 4 controllers per system, the 3ware 8000 Series can scale capacity to over 12 TB (250 GB x 12 port x 4 controllers/system).

[circumflatulator]

shaggy8675: Your website is the only source that was found (BIG thanks to TheBlackMan) on the Internet where real-world people talk about their personal experiences using the XP RAID hack. Made me feel much better knowing others are successfully using it.

And thank you for the additional information! If everything goes well, this coming weekend I’ll have it up and running. I will report my findings/experience to you and you can add that info to the RAID0 and RAID1 data you already have posted there. However I don’t yet know how to do the performance benchmark data gathering, but I’ll figure it out.

What I am planning on doing is adding a new 4-port SATA controller board (PROMISE SATAII150 TX4) and 4 new 250GB SATA hard drives (WD 2500JD) to the computer and setting that up as a single 750GB RAID-5 volume. Then I will copy all the data from my 250GB music backup drive to the new RAID volume. Then I’ll reformat that music backup drive and try adding it to the RAID volume and make sure the music files are still there and usable. That way if there is a problem and I lose the data while adding a disk to the RAID volume, I’ll still have the mirror-copy of my music files on a separate drive – nothing will be lost. If that much works, then I’ll start copying all the files from my video disks, and then add those disks one by one to the RAID-5 volume. If I don’t run into any size or number of disks limitations, when all is done I should have a single 3TB RAID-5 volume! (Note: All the pre-existing drives are WD 2500XX drives, with the XX being either JD or PB or JB. All their specs are identical except some are IDE and the others are SATA. My understanding is that they can all be included in the same RAID-5 array using the XP hack.)

The only way I can see that I would lose my data is if I go to add another drive to the RAID volume and I run into some unpublished limit (trying to exceed a maximum-size-of-volume or maximum-number-of-drives-per-volume/array) and have the whole RAID array go into neverland. I guess that is the risk of using this hack as I’m sure Micro$oft won’t publish any specifications on this hidden feature built into XP.

On a side note, is there any reason to suspect that this hack is possible because XP uses core elements of Micro$oft Server (or visa-versa) and those unknown size limitations are the same as in SERVER? If that was the case, then some research on SERVER (2000 or 2003) should produce information on those unknown limits.

AGAIN – THANK YOU TO EVERYONE WHO POSTED TO HELP ME OUT!!!! I’ll try to reciprocate, but my knowledge is quite limited compared to most here on this site.

[jcarle]

@circumflatulator -

After a LOT of searching (a good hour worth), to get this information, and after extracting the important parts, you may want to take note of the following:

Basic disk storage supports partition-oriented disks. A basic disk is a physical disk that contains basic volumes (primary partitions, extended partitions, or logical drives). On master boot record (MBR) disks, you can create up to four primary partitions on a basic disk, or up to three primary partitions and one extended partition. You can also use free space on an extended partition to create logical drives. On GUID partition table (GPT) disks, you can create up to 128 primary partitions. Because you are not limited to four partitions on GPT disks, you do not have to create extended partitions on logical drives.

Dynamic disk storage supports volume-oriented disks. A dynamic disk is a physical disk that contains dynamic volumes. With dynamic disks, you can create simple volumes, volumes that span multiple disks (spanned and striped volumes), and fault-tolerant volumes (mirrored and RAID-5 volumes). Dynamic disks can contain an unlimited number of volumes.

You create dynamic disks when you use the Convert to Dynamic Disk command in Disk Management to change a basic disk.

Before you change a basic disk to a dynamic disk, note the following:

• You must have at least 1 megabyte (MB) of unallocated disk space available on any master boot record (MBR) basic disk that you want to change to a dynamic disk.
  
• When you change a basic disk to a dynamic disk, you change the existing partitions on the basic disk to simple volumes on the dynamic disk.
  
• After you change a basic disk to a dynamic disk, you cannot change the dynamic volumes back to partitions. You must first delete all dynamic volumes on the disk, and then change the dynamic disk back to a basic disk.
  
• Windows Server 2003 operating systems, Windows XP Professional, and Windows 2000 support dynamic disks. After you change a basic disk to a dynamic disk, you can only access the disk locally from these operating systems.
  

If you want to increase the size of a simple or spanned volume after you create it, you can extend it by adding unallocated free space on the dynamic disk.

• You can only extend NTFS volumes or volumes that do not yet contain a file system.
  
• If you upgraded from Windows 2000 to Windows Server 2003 (or to Windows XP Professional), you cannot extend a simple or spanned volume that you originally created as a basic volume and then changed to a dynamic volume in Windows 2000.
  
• You cannot extend the system or boot volume.
  

A RAID-5 volume is a fault-tolerant volume in which data and parity is striped across three or more physical disks. If part of one physical disk fails, you can recover the data on the failed disk by using the data and parity information on the functioning disks. With this technique, you need a minimum of three hard disk to set up fault tolerance.

Windows uses 32-bit block numbers in the lower storage stack. This effectively limited support for single disk devices-which might be hardware RAID sets, sometimes called virtual disks or LUNs-to being no larger than 2 terabytes (TB). To get storage unit sizes beyond 2 TB, one has to combine multiple LUNs using the Volume Manager, leading to a volume limit of 64 TB with RAID-0 or spanning or 62 TB with RAID-5. RAID-1 is also limited to 2 TB. The use of Volume Manager sets, however, imposes a performance penalty and can make some storage management scenarios difficult or impossible.

In contrast, the file system uses a 64-bit signed byte offset. This means that the absolute file system limit is actually 254 512-byte blocks. However, NTFS reduces this, because it supports a 32-bit cluster number * 64K per cluster maximum, which equals 256 TB.

Sources:

KB323442: HOW TO: Use the Disk Management Snap-in to Manage Basic and Dynamic Disks in Windows Server 2003

KB298155: HOW TO: Set Up Fault-Tolerant Sets on Dynamic Disks in Windows 2000

Large Logical Unit Support and Windows Server 2003 SP1

So essentially, you can have an unlimited amount of physical hard drives in your RAID-5 volume. It should be possible to make the volume go up to a maximum 256TB, though on Windows XP Service Pack 2, it may stop at a limit of 2TB. To be very sure (and not have to start all the work over again), I'd recommend that you build your storage array on Windows Server 2003 to insure that your limit really is 256TB. Though, if you DO continue to set this up using Windows XP, please let me know if you pass the 2TB limit. I'd really be curious to know since I don't have access to that kind of storage myself.

Edited July 31, 2005 by jcarle

[circumflatulator]

jcarle: EXCELLENT information. I believe you have answered the last remaining question I had: How big do I dare try to build any single LUN in the RAID array before running into a limitation = 2TB. Then I can just build another 2TB LUN, and so on.

This is important information as once I get all my data into the RAID array, the original disks that held that data will have themselves been integrated into the array. Then if the RAID LUN were to crash when I tried to exceed the 2TB limit, ALL my data would be lost (Aggghhh!) That is my worst fear.

And I agree that going the Server 2003 route would be a superior choice, but I cringe at the thought of wiping my system drive and installing a new OS (I know, an irrational fear – but that scares me for some reason. Maybe its because for the first time ever, I actually have come to trust a piece of software coming out of Micros***, as this XP SP-2 I’m running has never glitched, blue-screened, or given me the slightest hiccup. Maybe that’s because it has never been connected to the Internet and I have NO plans to implement any Micro$oft upgrades/updates in the future.)

However if, for some insane reason, I decide to TRY and add more than 2TB to a single LUN, I’ll definitely post the results here and on shaggy’s site.

Thanks, big-time.

[jcarle]

Windows Server 2003 Enterprise Edition is like a rock-solid, more powerful version Windows XP. It's actually very secure as well. They actually got smart with 2003 and it's configured by default for security. I've been running it for a while at my client's store and I'm in love with it's stability, power and flexibility.