Intel Matrix RAID

Diagram of a Matrix RAID setup

Matrix RAID is a computer storage technology marketed by Intel. It is a firmware RAID system, rather than hardware RAID or software RAID.

Matrix RAID first appeared in the ICH6R "southbridge" chip. Intel uses an 'R' at the end of the southbridge's name – ICH9R instead of ICH9 – to indicate when a southbridge contains their Matrix RAID technology and no other upgrades. Complicating the matter is that instead of "R," a "DO," "DH," etc. has indicated a southbridge that combined RAID with non-RAID-related upgrades to the southbridge. Note that newer chipsets which don't use a separate southbridge might also use Intel RST without explicit extensions like "R" within the chipset name, an example for this is the Intel PCH C200 chipset series. Like all RAID, Intel Matrix RAID employs two or more physical hard disks which the operating system will treat as a single disk, in order to increase redundancy which avoids data loss (as all RAID levels except RAID 0 do), and/or to increase the speed at which data is written to and/or read from a disk.

Intel Matrix RAID is not a new RAID level. One of the features that Intel Matrix RAID has, which many other RAID implementations lack, is that different areas (e.g. partitions or logical volumes) on the same disk can be assigned to different RAID devices. The ICH10R supports Standard RAID levels RAID 0, RAID 1, RAID 10, and RAID 5.^[1]

Intel recommends to put any critical applications and data on a RAID 1, 5, or 10 volume. The thinking being that protection from losing the user's personal data and the OS and program configuration settings is more important than having the pure performance (speed) increase of RAID 0. On the other hand, the RAID 0 volume in Matrix RAID is recommended mostly for working with large files, such as videos during editing, and for non-critical files where fast storage will increase performance (swap files, for example, or read-only files that are backed-up on a separate PC).

Intel Matrix RAID, along with Intel Rapid RAID and Intel Smart Response Technology, are features of Intel Rapid Storage Technology.^[2]

Operating system support

Linux supports Matrix RAID through device mapper (DM-RAID) for RAID 0, 1 and 10, and MD-RAID for RAID 0, 1, 10, and 5. DM-RAID does not provide a graphical utility to configure the arrays or notify the user of disk errors/failures, and will not activate the Intel Matrix RAID on many motherboards (due to incompatibilities).^{[citation needed]} Set up of the RAID volumes must be done by using the ROM option in the Matrix Storage Manager, then further configuration can be done in DM-RAID or MD-RAID.^[3]

FreeBSD and MidnightBSD support Intel Matrix RAID using the ataraid driver, managed through the atacontrol command.^[4][5] However, with older versions of FreeBSD there are critical reliability issues which include array device renaming when a disk in an array is replaced,^[6] an array being considered healthy if the machine reboot/crashes during an array rebuild,^[7] and kernel panics when a disk is lost or is removed from the bus.^[8][9] Some of these problems, when experienced in combination, could result in the loss of an entire array (even in the case of RAID 1).

Microsoft Windows has full support for Intel Matrix RAID, including creation of RAID volumes.

VMware ESXi 4 does not support any RAID function nor Intel Matrix RAID based on Intel ICHxR controllers.^[10]

PGPDisk does not support Intel Matrix RAID based on Intel ICHxR, and does not support standalone drives if the "RAID" mode is enabled on the motherboard.

Matrix Storage Manager option ROM

Intel's Matrix Storage Manager option ROM is a part of Matrix RAID that has to be used in the BIOS to create new RAID arrays.^[11] Intel uses "Rapid Storage Technology" -"Option Rom"- on its newest chipsets, dropping the Matrix name.^[12][13] Intel's support NOTE states (Intel Rapid Storage Technology (formerly Intel Matrix RAID) showing how the Matrix storage changed to RST (Rapid Storage Technology).^[14]

There are several versions available:

Since release 11.2.0.0000, TRIM commands can be read by the RAID controller in 7 series chipsets. There is no TRIM support in older chipsets.^[19]

The newest release of Rapid Storage Technology Driver is 12.7.0.1022 non-WHQL,^[20] Rapid Storage software storage system download 12.0.0.1083. The newest RAID Option ROM contained in the BIOS is 12.7.0.1936 (non-WHQL), of which all can be found at Station Drivers.^[21]

Intel states that RST support has been added for the X79 chipset in RST version 11.6.0.0000 and after. Contained in the RST Production Version Release Notes, contained here.^[22]

On some 6 series chipsets there is a Modification which will add a modded ROM to the BIOS which will allow TRIM support on the 6 series chipset, contained here.^[23]

For the X79 chipset, certain Motherboard MFG's have added both RAID ROM's in the BIOS, the RST and RST-E ROM. X79 is the Enterprise version, called RST-E. With the RST ROM added to the BIOS, this allows TRIM function to pass through the controller and TRIM SSD drives. As there is no support for TRIM with the RST-E version of the ROM. If the motherboard manufacturer has not added the RST ROM to your BIOS, you can mod the BIOS with a modified ROM for the X79, that only contains the RST-E ROM.^[24]

The Intel RAID ROM is the firmware in the motherboard BIOS that is used to create the RAID array.

NOTE: The RST drivers can be used for RAID and also on a single drive as it contains an AHCI driver. There is a BUG in the version 12.5.0.1066 RST driver, which cause TRIM commands NOT to pass through the controller to the drives. TRIM is disabled using this driver.

See also

• RAID
• Standard RAID levels
• Non-standard RAID levels
• Smart Response Technology

References

• Ben Freeman (May 7, 2004). "Storage Basics: Choosing a RAID Controller". Enterprise Storage Forum.com. 

This article is based on material taken from the Free On-line Dictionary of Computing prior to 1 November 2008 and incorporated under the "relicensing" terms of the GFDL, version 1.3 or later.

External links

• "Intel Rapid Storage Technology". Support download website. Retrieved November 5, 2011. 

http://www.software-driver.com/dell/dell-inspiron-14-7437-intel-rapid-storage-technology-driver-for-windows-8-64bit/