20 March 2008

Guide for installing and configuring Raid!!


With the advent of onboard raid controllers becoming more mainstream, I thought a guide for installing and configuring raid might be helpful. First a short discussion on what raid can do for you and what it will not do for you.

First and foremost, raid is NOT a backup solution. While Raid-1, Raid-01, or Raid-5 offer some degree of backup in regard to a hardware failure, it does nothing if you get a virus, bad driver install, etc. What raid can do for you is to offer either some performance increase [generally around 35-40%] in regard to disk read/writes OR some protection for a failed hard disk.

If you think you would like to try running raid, the first thing to decide is what type of raid you want. The options here are as follows.

Raid-0.
Raid-0 offers only a performance increase; there is NO redundancy in regard to hardware. A failure of one drive will result in the loss of ALL data on the array. Again backups cannot be stressed enough. Raid-0 does have the advantage that you do not loose disk space. If you use two drives of 120gig, you have an array of 240gig. The advantage here is performance only.

Raid-1.
Raid-1 offers the advantage of recovery in the advent of a disk failure. If one drive of a Raid-1 array fails, you replace the failed drive and restart. Enter the raid bios and rebuild the array. Use of Raid-1 will result in no performance increase AND the loss of ½ of your disk space. If you use the same two 120gig drives in Raid-1, you end up with an array of 120gig. Note there can be a slight decrease in disk performance since everything must be written twice.

Raid-5.
Raid-5 offers the advantage of both speed increase and the ability to recover from a single drive failure. With Raid-5, you will loose some of your disk space. With three 120gig drives, you have a 240gig array. Raid-5 is not generally as fast as Raid-0 however loss of one drive does not result in complete data loss. There are other variants of Raid however those are the most popular so that is what I will deal with here. Note many onboard type controllers only support Raid-0, Raid-1, or sometimes Raid-01. Often if you want Raid-5 you must buy a real raid card. If you have not ordered your motherboard yet, now would be a good time to do a little research and see if the board you are considering will support the type of Raid you want to run.With that out of the way, we can continue with setting up our array. Again I always recommend using drives of the same size, speed, and cache size.

Step 1 Connect your drives to the controller. If you have an older ide type raid controller, each drive should be jumpered as master on its own ide channel. As an example you connect your first drive to ide1 on your controller and your second drive to ide2 on your controller. Set jumpers as master on both drives. Connect power to the drives.If you have sata type drives, you simply connect the drives to the controller and connect power. The only jumper on a sata drive is for speed limiting. If your controller only supports sata1 and you have sata2 drives, then you should set the speed limit jumper.

Step2 If you have an onboard type controller ie it came on your motherboard, you must set the controller mode to raid. This is done in the system [not raid] bios. As each bios is different you must read your manual as to how to set the controller mode. Note if you are using a real raid card such as a promise, highpoint, adaptec, etc. You do not need to set the mode.

Step3 Select your drives. Restart your system and enter the raid [not system] bios. To enter the raid bios you will hit a key combo. Popular key combos are Ctrl>I for intel, Crtl>H for highpoint, Crtl>F for promise. Again read your manual. Once in the Raid bios you will see your drives. Select to create an array. Next is what type of array; Raid-0, Raid-1, etc. Note this is often called stripe or mirror; again read the manual. Next step you will add drives to the array. Generally this is just highlight each drive you want to add and hit enter. Once done with that task you will create the array.

Step4. Make the array bootable. Most raid bios default to this however highpoint does not do this. You must select the array and select the option to make bootable. Restart the system and enter the system bios [not the raid bios] make sure your array or your add-in card is listed as the boot drive / device. While in the bios set the CD as the first boot device. Save settings and exit.

Step5 Partition and format the array. Now we are ready to install an operating system. Insert your win2k, xp, or vista cd/dvd in the drive and restart. Note for win2k or xp, you MUST have the Raid driver on a floppy disk. If you are installing vista, there is a very good chance vista will have drivers for your controller. I know it has promise and intel drivers; I have not installed it on any other raid controllers. During the first part of setup for win2k or xp you will have to hit the F6 key to load the driver. Note often a motherboard will come with either a driver floppy OR your support CD has an option to make a driver disk. Real Raid cards come with a driver floppy. Once you load the driver, you will see your Raid array displayed on the “Where to install menu page” You will need to create one or more partitions and format with ntfs.

Since many new systems are built without a floppy drive, here are two alternate methods of coping with the need to load the raid drivers.

First method.If your current install of windows is working fine without problems, you can clone it to your Raid array. To do this connect the drives and create the array as previously. Leave your current drive [with operating system and apps, etc] connected for now. Make sure you have the Raid controller installed and showing that it is operating correctly in device manager. Now boot your system with your cloning app. I use and recommend Acronis True Image for this task. Choose the source [old drive] and destination [new raid array] During this part Acronis will give you the option to retain your current partition size, to keep the same percentage, or it will allow you to resize the partitions. Note this must be in expert or manual mode to do this. Once you are sure of partition sizes, etc, complete the clone process. Now shutdown and disconnect your old drive. Note you can just pull the power connector from the drive. VERY IMPORTANT do not reboot with the old drive and the array connect; this WILL result in drive letter problems. Restart the system and make sure it will boot, drive letters are correct, etc. Once you are sure all is well, you can shutdown and reconnect your old drive; windows will assign the next available drive letter to the old drive. Note if the old drive was ide, many motherboards will default to that drive as the boot drive. Before you let windows boot with the old drive connected, enter the bios and make sure the Raid array is listed as the boot drive.

Second method.This option requires you to make a slipstreamed windows install disk with the raid drivers integrated into the install disk. There are various apps to choose from to accomplish this task. The only one I have used for this is Nlite. It does work well however you must have .NET installed to use Nlite. Slipstreaming is a whole guide on its own so if you want to use this method, you need to do some reading on your own. FWIW I have made custom install disks with win2k or xp for nvidia, promise, and highpoint controllers. This method works very well.

Once the raid driver is loaded during setup, it is no different than loading windows on any drive.You now have a raid array and either increased disk performance or increased hardware redundancy.
Congratulations!!!!!


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--Imagination is more important than knowledge. - Einstein

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