Monday, January 1, 2007

Happy New Year!

Let's recap what I have done to the disk set-up on Nighthawk to date:

  1. At initial assembly, I installed two Maxtor SATA-2 500GB drives.
  2. Set the ICH8R Controller to RAID (in BIOS 0804, SATA Configuration as "Enhanced" and Configure SATA as "RAID."
  3. Left the two drives as non-RAID.
  4. Installed Windows XP MCE 2005 on disk #1 (with the other disk unused and reserved for Windows Vista).
  5. Created a RAID array using both drives and migrated Windows XP MCE 2005 to a RAID0 volume which utilized half of the space on the array.

What to do with the remaining space on the RAID array?

I started the Intel(R) Matrix Storage Console and selected the "Create RAID Volume" action. I was greeted by the Create RAID Volume Wizard with the following messages (I highlighted the key words I focused on):

This wizard creates a RAID volume across hard drives or across available space on an existing array.

WARNING: Creating an initial RAID volume will permanently delete existing data on the selected hard drives or array. Back up all important data before continuing.

In order to preserve the existing data on a hard drive, use the 'Create RAID Volume from Existing Hard Drive' action instead.

The warning message caused me to pause and re-read the messages several times very s-l-o-w-l-y to make sure I understood the implications of what I was about ready to do.

I pressed 'Next' to continue and the 'Configure Volume' dialog was displayed. I specified "Nighthawk_VISTA" as the Volume Name. Note that the RAID Level allowed me to select RAID 0, RAID 1, RAID 10 or RAID 5.

That is very interesting. RAID 0 and 1 make sense since the existing RAID array consists of 2 physical drives. RAID 10 requires 4 physical drives and RAID 5 requires at least 3 physical drives (and a maximum of 4 physical drives on this controller). So, why is RAID 10 or RAID 5 an option here?

I selected RAID 0, the default Strip Size of 128 KB and pressed 'Next.'

The "Select Volume Location" dialog was then displayed. Only the existing array with available space was displayed as an option. However, I believe that if there were additional physical drives and/or other arrays with available space, they would show up here.

I was relieved to read the following message in the dialog box:

WARNING: Selecting hard drives will permanently delete the data on the hard drives. Backup all important data before continuing.

Since I selected an existing array (Array_0000) with available space and not hard drives, I felt relatively safe from losing any data.

The "Specify Volume Size" dialog was displayed after I clicked on 'Next.'

However, every input field was 'grayed out' in the dialog box. I can only conclude that there is a maximum of 2 RAID volumes in a RAID array. I had presumed otherwise prior to starting this exercise.

I clicked 'Next' and I believe there was a confirmation dialog which I failed to capture during the 'heat of the moment.'

Almost instantaneously, the RAID 0 volume was created and Windows XP MCE 2005 detected the 'new hardware.'

So Nighthawk now has 2 RAID 0 volumes (Nighthawk_XP_MCE and Nighthawk_VISTA) on a RAID array (Array_0000) consisting of 2 physical drives.

The 2 RAID volumes could also have been both RAID 1 or a combination of one RAID 0 volume and one RAID 1 volume.

I believe that the ability to create multiple RAID volumes (maximum of 2, it appears) in the same RAID array is the reason for the "Matrix" in the Intel(R) Matrix Storage name. My previous understanding of RAID technology was limited to RAID arrays and physical drives with an array equivalent to a volume.

My next steps are to get the Plextor PX-755SA optical drive working by connecting it to the ICH8R controller instead of the JMicron controller and to disable the new RAID 0 volume (Nighthawk_VISTA) in Windows XP MCE 2005. I do not want Windows XP MCE 2005 to "see" (and possibly corrupt) Windows Vista Ultimate x64 (RTM Build 6000) when it is installed on Nighthawk_VISTA.

It also appears that Nighthawk has been very stable running at 3.0GHz so I will be overclocking it to 3.2GHz ahead of schedule.

Before I conclude my posting today, I want to quickly return to the ICH8R Controller. I am running 2 RAID arrays (one RAID 5 volume on each) with 3 Seagate 750 GB disk drives on each on my other system, Blackbird. I selected RAID 5 because of it provides the maximum insurance against loss of data due to a physical drive failure at the lowest cost.

One of the lessons I have learned about setting up a critical system where loss of data (whether on a RAID or non-RAID set-up) is unacceptable is to make sure that one has a good backup and recovery plan. I think everyone knows this, but I am always amazed at how many people do not bother to test their backup and recovery plan until they need it.

I have tested my backup and recovery plan for Blackbird since it is my "production" system. I have tested the ICH8R controller's ability to recover from a single disk drive failure by deliberately taking one physical drive in a RAID 5 array off-line (with the system powered off, of course), starting the system (the controller detects the missing drive and shows a "degraded" RAID status), stopping & powering off the system, placing the disk back on-line, and restarting the system.

Repairing the "degraded" RAID array is simple with the Intel(R) Matrix Storage Console and you can continue working with the system while the array is being repaired. The repair process barely uses CPU resources and system performance remains good. It takes almost 48 hours to repair a RAID 5 array consisting of three 750 GB disk drives! But the good news is that the ICH8R Controller is up to the task.

Before I conclude this post, I would also like to share 2 other things I have found with the ICH8R Controller:

  1. Since the operating system no longer "sees" the physical disk drives in a RAID set-up, the OS loses its ability to monitor the health of the drives using S.M.A.R.T. but the Intel(R) Matrix Storage Console performs this. Unfortunately, it does not display the temperatures of the disk drives so you will lose the ability to monitor disk drive temperatures in a RAID set-up.
  2. Once you have defined your RAID array(s), you can safely move the SATA connections to your physical drives around in the 6 SATA ports without any impact to your RAID set-up.

That's it for today!

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