Could someone please xplain to me who would benefit from RAID? Mirroring your HDD sounds like a great idea but consultants laigh at me when I tell them that I am a Home user. They say :"No....you don't want to do this!". Is it the cost or is it really overkill? It is NO fun to lose your hard drive to a virus or mechanical failure why shouldn't the Home User benefit? I was told that RAID takes time to perform the backup and you cannot shut the computer down while in action etc... All I need to know is who would use RAID and if it is as cumbersome as it sounds.
Thanks!

I am not a fan of RAID, so I can't tell you much about it. I do know that it isn't likely to be much help if you mirror when you are hit by a virus. The virus would get mirrored too, so you would have to clean up both drives before you were done.

There is another RAID option which allows for more speed, but I have heard mixed reviews about the value of that as well. Overall, it always sounds to me like it might be interesting to set a RAID array up for the sake of learning more about my system and to see if I could make it work, but it probably wouldn't really add anything to my daily computing practice....

Budfred.....well put, I appreciate your honesty and will keep it in mind!

The 2 most common versions of RAID are 0 and 1. RAID0 is striping. In this mode data is written or read alternately from the drives( a sector from drive1 then one from drive2) This allows the drives to be used more efficiently. This provides a performance boost for gamers or anyone looking for maximum speed.
In RAID1 (mirroring) all data is written to both drives. This provides data redundancy and protects against drive failures. This is usually used on servers where data and uptime are critical.

There are also some other types, like mirroring and striping combined.

Most often for normal every day use RAID is overkill. If you want to do some serious editing, then it can be useful.

Mirroring your HDD sounds like a great idea but consultants laigh at me when I tell them that I am a Home user. They say :"No....you don't want to do this!".I hate it when computer "experts" do that! :mad: If you're willing to learn and try things out, I see no reason why you shouldn't be free to do so. Besides, there are many "home users" that are seeing definite benefits to using RAID. I'm not saying you need it, but if you feel like giving it a try after researching it, then by all means, go ahead.

RAID stands for "redundant array of independent disks". Basically, RAID is a way of using 2 or more physical hard drives at once to improve data integrity or speed or both.

RAID0 (zero) for instance would take two 80GB drives and make one 160GB partition. This provides the best speed boost but at the cost of higher risk of data loss. If either drive fails, everything is gone. Speed gains are often on the order of 30-70%, depending on the task. For relatively unimportant data where speed is valued above all, RAID0 is used.

RAID1 (one) would take two 80GB drives and make one 80GB partition. This provides no speed boost (sometimes it can even decrease speed by 2-5%) but provides the best in data protection. If one drive fails, everything is still safe. For very important data, RAID1 is used, sometimes with many drives (like 4 or 6 or even a whole storage cabinet!).

RAID5 is a hybrid of 0 and 1 that uses an odd number of drives. Three 80GB drives would be used to create, say, a single 200GB partition. The rest of each drive would be used for parity information (the exact amount can be adjusted). This provides a decent speed boost while also protecting against the loss of a drive. RAID5 fails, however, if 2 drives are lost (or a majority like 4 out of 7, 5 out of 9, etc).

RAID0+1 is a straight up combination of 0 and 1 that requires at least 4 drives. It's exactly as it sounds, with 2 drives striped and 2 mirrored. The cool thing is you get almost the speed boost of RAID0, but with data protection, too. For instance, RAID0+1 can survive if the two mirrored drives are lost, but if 2 of the striped drives are lost (ie they have the same data on them) then the whole array comes down. Very peculiar if you ask me... RAID1+0 is essentially the same except for the order of the drives (ie mirrored drives first, then striped).

As for the other stuff you mentioned about setting one up, it's easy. Most mobo's these days have RAID capability built into them, so all you need is to choose which RAID version and which hard drives to use. The rest of the directions are often straight-forward and a whole lot easier than a few years ago. Backing up a RAID array is also no different than any other drive because the OS "sees" the whole array as one partition, just like a normal hard drive. As for "not shutting the computer down while in action"? I'm confused. Last I checked, it wasn't a good idea to shut any computer down while it's accessing the hard drive(s). Would you turn off your PC while it was loading a program or game? Of course not! I think these "consultants" were just scaring you away from RAID because they assumed you would have no need for it. Unless they spent some time actually listening to you and your computing habits, I say ignore them.

This was an awesome response, thank you for your wisdom!

When does the actual mirroring happen? Is it constant or is it a command that you perform at the end of the day?

I am pretty sure it is an ongoing process which is why it won't protect you from virus infection... The idea is that if the hard drive crashes at any moment, your data is preserved on the redundant drive...

RAID happens in real-time. It's a one-time configuration and is controlled by the RAID controller chip. It's completely different from something like a tape back-up, which requires either user intervention or software. RAID is run in pure hardware and needs no maintainance once you have it set up (unless a drive fails :p).

The input was great from all of you and the critical bit was the fact that since RAID does work on its own, it would make it vulnerable to a virus, but a great way to back things up!

IMHO running two HDDs as a RAID1 (mirror) has definite advantages in securing ones data. Not only does it safeguard against mechanical failure of one drive but it also means that the downtime is negligible in the event of such failure of one of them.

I can emulate this by just pulling the cable from one of the two mirrors. There is then a Critical Warning about a failed drive but the system continues to function quite normally on the remaining drive. When the replacement is obtained (in this instance by reconnecting the cable) the array is rebuilt at the next boot up and the mirroring is continued normally.

OK - so it doesn't protect against viral infections or indeed accidental deletion of ones own files but there are other fairly good safeguards against doing this or of recovering such data if need be. Recovering data from mechanically failed drives is prohibitively difficult and expensive.

All I know about backing up - is that if it's not easy or semi-automatic it nearly always gets forgotten about until too late. Others will have their own methods and will have data of little or very great importance. Because its quick and easy I make image files on a large third HDD on a regular basis (in addition to my two-drive RAID 1) and copy the most important data to removable media as necessary.

It's not the only way to do things - some just love tape backup - but for me it works because it's easy enough and quick enough to actually get done regularly. And having a store of images on a HDD makes recovery and restoration quick and easy as well.

Not all RAID setups will improve performance for most desktop applications.

However, truely, high-speed Ultra-wide SCSI controllers mated to 10000+ rpm SCSI disks will indeed seem snappy.

I doubt the "IDE" play-time setups really do much.

A good video sub-system and control of application resources, with a big ATA 100 drive is about all you can play with at the desktop level.

What about Western Digital's 10,000rpm SATA drive? It was designed for server duties but it's SATA so it works in desktop systems. I heard someone took two of those things and put them in RAID0 - they installed Windows in less than 10 minutes! :D

And since SATA is built into the southbridge on the latest Intel chipsets, you will realistically see almost as much performance out of a SATA RAID array as most PCI-based SCSI arrays.

Besides, even if it's only "playing" on the desktop level, the results aren't too shabby and certainly suffice for most "home" users' needs. If not, they get their own multi-CPU server. ;) Hey, if you've got the money, you don't have to be a small business to buy a server!