SAS RAID Controllers for IBM I

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SAS RAID Controllers for IBM I Power Systems SAS RAID controllers for IBM i Power Systems SAS RAID controllers for IBM i Note Before using this information and the product it supports, read the information in “Notices,” on page 57, “Safety notices” on page v, the IBM Systems Safety Notices manual, G229-9054, and the IBM Environmental Notices and User Guide, Z125–5823. This edition applies to IBM Power Systems™ servers that contain the POWER6® processor and to all associated models. © Copyright International Business Machines Corporation 2009. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Safety notices .................................v Chapter 1. What’s new in SAS RAID controllers for IBM i ..............1 Chapter 2. SAS RAID controllers for IBM i .....................3 Feature comparison of SAS RAID cards ..........................3 PCI-X SAS RAID card comparison ...........................3 PCIe SAS RAID card comparison ...........................6 SAS architecture ..................................8 Disk arrays ....................................9 Supported RAID levels ..............................10 RAID 5 ...................................10 RAID 6 ...................................11 System mirroring ...............................11 Disk array capacities ...............................11 RAID level summary ...............................12 Valid states for disk arrays and physical disk units ......................12 States for disk arrays ...............................12 States for disk units ...............................13 Auxiliary write cache ................................13 Auxiliary write cache adapter ............................14 Viewing link status information ...........................15 Chapter 3. Controller software .........................17 Verifying the controller software ............................17 Chapter 4. Common controller and disk array management tasks ..........19 Viewing IBM SAS disk information ...........................19 Considerations for solid-state drives ...........................19 Chapter 5. Dual storage IOA configurations ....................21 Possible disk storage IOA configurations .........................21 Dual storage IOA functions ..............................22 Dual storage IOA function attributes ...........................24 Viewing dual storage IOA attributes ...........................24 SAS cabling considerations ..............................25 Performance considerations ..............................26 Dual storage IOA access optimization ..........................26 Installing dual storage IOA configurations .........................28 Chapter 6. SAS RAID controller maintenance ...................31 Rechargeable battery maintenance ............................31 Displaying rechargeable battery information .......................31 Error state ...................................33 Forcing a rechargeable battery error ..........................34 Replacing a battery pack ...............................34 Replacing a 572B nonconcurrent maintainable battery pack ..................35 Replacing a 57B7 concurrent maintainable battery pack....................37 Replacing a 574E concurrent maintainable battery pack....................38 Replacing a 572F/575C card set concurrent maintainable battery pack ...............39 Separating the 572F/575C card set and moving the cache directory card ...............40 Viewing SAS fabric path information ...........................45 Example: Using SAS fabric path information ........................49 © Copyright IBM Corp. 2009 iii Chapter 7. SAS address and physical location information .............55 Appendix. Notices ...............................57 Trademarks ...................................58 Electronic emission notices ..............................58 Class A Notices .................................58 Terms and conditions ................................62 iv SAS RAID controllers for IBM i Safety notices Safety notices may be printed throughout this guide: v DANGER notices call attention to a situation that is potentially lethal or extremely hazardous to people. v CAUTION notices call attention to a situation that is potentially hazardous to people because of some existing condition. v Attention notices call attention to the possibility of damage to a program, device, system, or data. World Trade safety information Several countries require the safety information contained in product publications to be presented in their national languages. If this requirement applies to your country, a safety information booklet is included in the publications package shipped with the product. The booklet contains the safety information in your national language with references to the U.S. English source. Before using a U.S. English publication to install, operate, or service this product, you must first become familiar with the related safety information in the booklet. You should also refer to the booklet any time you do not clearly understand any safety information in the U.S. English publications. German safety information Das Produkt ist nicht für den Einsatz an Bildschirmarbeitsplätzen im Sinne§2der Bildschirmarbeitsverordnung geeignet. Laser safety information IBM® servers can use I/O cards or features that are fiber-optic based and that utilize lasers or LEDs. Laser compliance All lasers are certified in the U.S. to conform to the requirements of DHHS 21 CFR Subchapter J for class 1 laser products. Outside the U.S., they are certified to be in compliance with IEC 60825 as a class 1 laser product. Consult the label on each part for laser certification numbers and approval information. CAUTION: This product might contain one or more of the following devices: CD-ROM drive, DVD-ROM drive, DVD-RAM drive, or laser module, which are Class 1 laser products. Note the following information: v Do not remove the covers. Removing the covers of the laser product could result in exposure to hazardous laser radiation. There are no serviceable parts inside the device. v Use of the controls or adjustments or performance of procedures other than those specified herein might result in hazardous radiation exposure. (C026) CAUTION: Data processing environments can contain equipment transmitting on system links with laser modules that operate at greater than Class 1 power levels. For this reason, never look into the end of an optical fiber cable or open receptacle. (C027) CAUTION: This product contains a Class 1M laser. Do not view directly with optical instruments. (C028) © Copyright IBM Corp. 2009 v CAUTION: Some laser products contain an embedded Class 3A or Class 3B laser diode. Note the following information: laser radiation when open. Do not stare into the beam, do not view directly with optical instruments, and avoid direct exposure to the beam. (C030) Power and cabling information for NEBS (Network Equipment-Building System) GR-1089-CORE The following comments apply to the IBM servers that have been designated as conforming to NEBS (Network Equipment-Building System) GR-1089-CORE: The equipment is suitable for installation in the following: v Network telecommunications facilities v Locations where the NEC (National Electrical Code) applies The intrabuilding ports of this equipment are suitable for connection to intrabuilding or unexposed wiring or cabling only. The intrabuilding ports of this equipment must not be metallically connected to the interfaces that connect to the OSP (outside plant) or its wiring. These interfaces are designed for use as intrabuilding interfaces only (Type 2 or Type 4 ports as described in GR-1089-CORE) and require isolation from the exposed OSP cabling. The addition of primary protectors is not sufficient protection to connect these interfaces metallically to OSP wiring. Note: All Ethernet cables must be shielded and grounded at both ends. The ac-powered system does not require the use of an external surge protection device (SPD). The dc-powered system employs an isolated DC return (DC-I) design. The DC battery return terminal shall not be connected to the chassis or frame ground. vi SAS RAID controllers for IBM i Chapter 1. What’s new in SAS RAID controllers for IBM i This topic collection is new for the October 2009 release. © Copyright IBM Corp. 2009 1 2 SAS RAID controllers for IBM i Chapter 2. SAS RAID controllers for IBM i Find usage and maintenance information regarding controllers for the serial-attached SCSI (SAS) Redundant Array of Independent Disks (RAID) for IBM i. Use this information with your specific system unit and operating system documentation. General information is intended for all users of this product. Service information is intended for a service representative trained on the system unit and the subsystem being serviced. The SAS RAID controllers for IBM i have the following features: v PCI-X 266 system interface or PCI Express (PCIe) system interface. v Physical link speed of 3 Gbps SAS that supports transfer rates of 300 MB per second. v Support for SAS devices and nondisk Serial Advanced Technology Attachment (SATA) devices. v Optimized for SAS disk configurations that use dual paths through dual expanders for redundancy and reliability. v Controller managed path redundancy and path switching for multiported SAS devices. v Embedded PowerPC® Reduced Instruction Set Computer (RISC) processor, hardware XOR Direct Memory Access engine, and hardware finite field multiplier (FFM) DMA engine for RAID 6. v Some adapters
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