Redundant Array of Independent Disks (RAID) on HP Compaq dc7700 and dx7300 Business PCs Using Intel Matrix Storage Manager Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Mirroring and Parity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Disk Striping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Basics of RAID Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Basic RAID Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 RAID 0 with two hard drives (Striped) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 RAID 1 with two hard drives (Mirror) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 RAID 5 with three hard drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Intel Matrix Storage Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Recommended configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 HP Backup and Recovery interactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Other supported configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Unsupported configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Configuring RAID on non-factory preinstalled configurations . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Enabling RAID through F10 System BIOS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Configuring RAID Option ROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Configuring RAID Volume using the Option ROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Notes for operating system installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Intel Matrix Storage Manager software installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Console Software Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Using the Intel Matrix Storage Console interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 RAID migrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 1 Migration to RAID 1 from two non-RAID hard drives using Intel Matrix Storage Console . . . 20 Degradation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Migration to RAID 0 from two non-RAID hard drives using Intel Matrix Storage Console . . . 23 Migration to RAID 0 from three non-RAID hard drives using Intel Matrix Storage Console . . . 24 Migration to RAID 5 from three non-RAID hard drives using Intel Matrix Storage Console . . . 28 Migration to Matrix RAID 5 and RAID 0 from three non-RAID hard drives using Intel Matrix Storage Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Migration to RAID Matrix Mode (0 + 1) from two non-RAID hard drives using Matrix Storage Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Language support table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 2 Introduction RAID (Redundant Array of Independent Disks) is a category of hard drives that employ two or more drives in combination for fault tolerance and performance. Initially used with servers, desktop PCs are increasingly using RAID by adding a RAID controller and extra IDE or SCSI disks. Newer system boards often have RAID controllers. RAID technology takes advantage of Serial Advanced Technology Attachment (SATA) and the integration of RAID into the Intel Q965/ICH8-D0 chipset. The HP Compaq dc7700 and dx7300 Business PC products are the first business desktops to incorporate RAID drive support through factory configurations. This white paper provides a basic overview of RAID technology, supported factory configurations of HP Compaq dc7700/dx7300 Business PCs, other supported RAID configurations, and basic instructions on how to migrate non-RAID to RAID configurations in the field. Mirroring and Parity Fault tolerance is achieved by mirroring or parity. Mirroring is 100% duplication of the data on two drives (RAID 1). Parity is used to calculate the data in two drives and store the results on a third drive (RAID 5). After a failed drive is replaced, the RAID controller automatically rebuilds the lost data from the other two drives. RAID systems may have a spare drive (hot spare) ready and waiting to be the replacement for a drive that fails. Disk Striping RAID improves performance by disk striping, which interleaves bytes or groups of bytes across multiple drives, so more than one disk is reading and writing simultaneously. Basics of RAID Technology Definitions Table 1 Basic RAID Definitions ATA BIOS Chipset HDD ICH IDE Advanced Technology Attachment. Basic Input/Output System, also known as system ROM. Term used to define a collection of integrated components required to make a PC function. Hard disk drive. Intel Input/Output Controller Hub, inside this component resides the mass storage controller. ICH is part of the Intel Q965 chipset. Integrated Drive Electronics. 3 INF Information file (.inf) used by Microsoft operating systems that support the Plug & Play feature. When installing a driver, this file provides the operating system needed information about driver filenames, driver components, and supported hardware. Term used to describe the movement of data from one configuration or usage model to another. Native Command Queuing. Piece or software module inside the System BIOS which provides extended support for a particular piece of hardware. The RAID Option ROM provides boot support for RAID volumes as well as a user interface for managing and configuring the systems RAID volumes. Peripheral Components Interface. PCI express. A serial version of PCI. Plug and Play. Redundant Array of Independent Disks. Read Only Memory. Serial ATA. Set of data on a single hard drive in a RAID volume. Group of all strips going horizontally across all the hard drive members of a RAID volume. Migration NCQ Option ROM PCI PCIe PnP RAID ROM SATA Strip Stripe Table 2 RAID Drives Mode RAID 0 RAID 1 RAID 5 RAID 0 + 1 Intel's Matrix Technology Purpose Striped for Performance. Mirrored for Protection. Parity for Accuracy. Mirrored and Striped. 4 logical drives on 2 physical disks, to emulate RAID 0 and 1. Minimal HDD Required 2 2 3 4* 2 * Not supported on HP Compaq dc7700 and dx7300 Business PCs. 4 NOTES: The following notes are important for RAID configuration: · · RAID 1 is the only RAID configuration that HP Compaq dc7700 and dx7300 Business PC products offer as factory configurations. The preconfigured systems: - Are complete RAID systems. - Have both drives installed. - Have the necessary Option ROM configuration. - Are preloaded and preinstalled with all required Intel software. - Include a preinstalled operating system that is mirrored mode out of the box. Basic RAID Types dx7300 Business PCs. This section provides a brief explanation of the supported RAID configurations for HP Compaq dc7700 and RAID 0 with two hard drives (Striped) Even though HP supports RAID 0, it is not the recommended configuration for business PC users. Lack of redundancy causes less than half the reliability of a single hard drive system since the Mean Time Between Failure (MTBF) of RAID 0 is equal to the MTBF of an individual drive, divided by the number of drives. Table 3 RAID 0 with two hard drives (Striped) First Disk Data Segment 1 Data Segment 3 Data Segment 5 Data Segment 7 Data Segment 9 Data Segment 11 Data Segment 13 Data Segment 15 Second Disk Data Segment 2 Data Segment 4 Data Segment 6 Data Segment 8 Data Segment 10 Data Segment 12 Data Segment 14 Data Segment 16 In the previous table, each "Data Segment n" represents a group of data, known as a strip. In this case, each row represents a stripe. RAID 0 represented in the table above shows how information is segmented, made into chunks or strips, and stored across the stripes of the hard drive members of this RAID volume. To better illustrate the concept of RAID 0 and striping, the following graphic shows how a sequence of data "ABCD..." is stored in a RAID 0 mode. In this example, each letter represents a segment or strip. The graphic shows how the various pieces of the information go to different hard drives. If any segment of RAID 0 fails, all information from all members is lost. 5 Figure 1 Performance - RAID 0 with two hard drives At a higher reliability cost with faster performance, HP Compaq dc7700 Business PC Convertible Minitower and dx7300 Microtower also allow for RAID 0 with three hard drives. RAID 0 with two or three hard drives is a supported configuration. RAID 0 with three hard drives is shown in the following figure: Figure 2 RAID 0 - Three hard drives 6 RAID 1 with two hard drives (Mirror) Because it is a very cost-effective way to increase system storage reliability and a great value proposition, RAID 1 is the only RAID configuration that HP preconfigures for HP Compaq dc7700 and dx7300 Business PCs. RAID 1 provides high availability with minimal performance impact, as well as greater reliability compared to a single hard drive configuration. RAID 1 has redundancy and hence is a true RAID. It more than doubles reliability because the MTBF of RAID 1 is equal to the MTBF of an individual drive multiplied by the number of drives (2). In other words, the probability of one hard drive failure on a given day is the square root of that same probability. Hypothetically, if the chances that a single hard drive fails is 1:2000, with RAID 1 the chance that both of your hard drives fail is 1:4,000,000. Mirroring, segmentation, and striping have no real meaning in RAID 1. In the table and graphic, the data is arranged in rows for representation of different pieces of data. Table 4 RAID 1 with two hard drives (Mirror) First Disk Data Segment 1 Data Segment 2 Data Segment 3 Data Segment 4 Data Segment 5 Data Segment 6 Data Segment 7 Data Segment 8 Second Disk Data Segment 1 Data Segment 2 Data Segment 3 Data Segment 4 Data Segment 5 Data Segment 6 Data Segment 7 Data Segment 8 In the previous table, each "Data Segment n" represents a group of data, known as a strip. In this case, each rows represent a stripe. This table shows how information is duplicated in both hard drives. The size of the strips is mostly irrelevant and not a configurable option. To better illustrate the concept of RAID 1 and mirroring, the following figure shows how a sequence of data "ABCD..." is stored in a RAID 1 volume. In this example, each letter represents a data segment. The graphic shows how the various pieces are replicated for both of the hard drives; hence, if any one member of the RAID 1 volume fails, the information is kept in the surviving members. After a hard drive failure, the user interface sends a notification so the failed hard drive can be replaced. No user information is lost in this scenario. 7 Figure 3 Reliability: RAID 1 - Mirroring RAID 5 with three hard drives RAID 5 has been used in servers for many years and is one of the most common types of RAID. RAID 5 uses striping with parity data in distributed blocks across all member disks. Therefore, the mass storage controller can simultaneously write new information to two hard drives and parity information to the third hard drive, so if one hard drive fails, the RAID controller can rebuild all the information after the volume degradation occurred. Hence, RAID 5 with three hard drives has similar performance to RAID 0 with two hard drives, and the reliability of RAID 1 with a minimum of three hard drives. 8 Table 5 RAID 5 with 3 hard drives (Parity) First Disk Data Segment 1 Data Segment 3 Parity for 5 and 6 Data Segment 7 Data Segment 9 Parity for 11 and 12 Data Segment 13 Data Segment 15 ...