EMC QLA23xx, QLA22xx manual Understanding Persistent Binding in a Fabric Environment

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Introduction

Understanding Persistent Binding in a Fabric Environment

Persistent binding is the mechanism to create a continuous logical route from a storage device object in the Windows host to a volume in the EMC® storage array across the fabric.

Without a persistent binding mechanism, the host cannot maintain persistent logical routing of the communication from a storage device object across the fabric to an EMC storage array volume. If the physical configuration of the switch is changed (for example, the cable is swapped or the host is rebooted), the logical route becomes inconsistent, causing possible data corruption if the user application is modifying data through inconsistent logical routing of the communication from the driver entry point to a volume in an EMC storage array across the fabric.

The Windows NT/Windows 2000/Windows 2003 operating system (OS) does not provide a satisfactory means to allow persistent binding. Most software applications access storage using file systems that are managed by the Windows OS. (File systems are represented by drive letters: colons: C:, D:, etc.) For storage devices containing file systems, Windows NT/Windows 2000 writes a Disk Signature to the disk device. The operating system can then identify, and associate with, a particular drive letter and file system.

Since the signature resides on the disk device, changes can occur on the storage end (a cable swap, for example) that can cause a disk device to be visible to the host server in a new location. However, the OS looks for the disk signature and, providing that nothing on the disk changed, associate the signature with the correct drive letter and file system. This mechanism is strictly an operating system feature and is not influenced by the Fibre Channel device driver.

Some software applications, however, do not use the Windows file systems or drive letters for their storage requirements. Instead they access storage drives directly, using their own built-in “file systems.” Devices that are accessed in this way are referred to as raw devices and are known as physical drives in Windows terminology.

The naming convention for physical drives is simple and is always the same for software applications using them. A raw device under Windows NT/Windows 2000/Windows 2003 is accessed by the name \\PHYSICALDRIVEXXX, where XXX is the drive number. For example, a system with three hard disks attached using a QLogic Fibre Channel controller assigns the disks the names

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EMC Fibre Channel with QLogic HBAs in Windows Hosts

 

 

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Contents REV A01 August Copyright 2001-2003 EMC Corporation. All rights reserved Trademark InformationContents Chapter Configuring an EMC Boot Device LUNProblems and Solutions Index Appendix B TroubleshootingAppendix a Third-Party Software EMC Fibre Channel with QLogic HBAs in Windows Hosts Damage to the system or equipment. The caution may apply to PrefaceEMC uses the following conventions for notes, cautions, Hardware or softwarePalatino Related Documentation Typographical ConventionsBold Introduction Understanding Persistent Binding in a Fabric Environment Understanding Persistent Binding in a Fabric Environment HBA Installing Configuring the HBA Driver Introduction Downloading QLogic Drivers Firmware Verifying DocumentationInstalling an HBA Check for an Updated HBA Driver Reconfigure the HBA Jumper Move the jumpers, onto pins 1-2 if not already thereSet the HBA FC-AL Loop ID Installing an HBA Settings EMC HBA SettingsPre-Configured Advanced Adapter Settings , and Extended Firmware SettingsConfiguring Nvram for Stratus ftServers To set the first HBA, follow these proceduresWith Embedded Firmware/BIOSFibre-Down Servers QLogic HBAsTo load firmware/BIOS and Nvram settings, type Example Flasutil /L /F /N NVRAM23o.DATPress the Down Arrow until you select Data Rate then press EMC HBA Settings Installing the HBA Driver Administrative Tools, Computer Management Select have DiskEMC Fibre Channel with QLogic HBAs in Windows Hosts Double-click the Scsi & RAID Controllers icon EMC Fibre Channel with QLogic HBAs in Windows Hosts Upgrading to Windows 2003 from Windows 2000 or Windows NT EMC Fibre Channel with QLogic HBAs in Windows Hosts Configuring an EMC Boot Device Configuring an EMC Boot Device How to Determine I/O Latency and Load on the Boot LUNSave to Disk Boot CrashdumpBehavior Configuring a Symmetrix Boot Device Select Current Boot Node Name and press Enter From the Configuration Settings menu, select Host AdapterFrom the Host Adapter Settings menu, select Host Adapter Configuration Settings menuWindows OS onto InstallingBoot Device Windows NTFrom this point, press S to specify additional devices HP ProLiant BL20p G2 Windows Installation Flowchart Configuring a CLARiiON Boot DeviceProcedure Installation procedure includes steps you must follow in aConfiguring a CLARiiON Boot Device Requirements, and related documentation Configurations, Revisions Hardware Software RequirementsRequirements TopologiesMedia Requirements Preparing the Storage SystemRequired media includes the following Press ESC to return to the previous menu Configuring a CLARiiON Boot Device EMC Fibre Channel with QLogic HBAs in Windows Hosts What Next? Node NameContinue to Preparing the Server on Preparing the Server Physical Connection of Only One SP Port to the FabricConfiguring the HP ProLiant BL20p G2 Select Set Boot Controller OrderConfiguring the HBA Boot BiosCTRL-Q G2 Windows 2000 OS Installation on Windows Licensing Agreement appears HP ProLiant BL20p G2 Windows 2000 OS Installation Verifying HBA Driver Digital Signature Installation EMC Fibre Channel with QLogic HBAs in Windows Hosts Additional Boot Port Installing AdditionalConfiguring Navisphere HostEMC Fibre Channel with QLogic HBAs in Windows Hosts Configuring a CLARiiON Boot Device Trespassing the Boot LUN Using atftrespass On the Computer Management window, click Disk ManagementStarting a Fresh Installation Boot Time and LUN Availability Replacing a Boot HBA EMC Symmetrix EMC CLARiiONStop Error fatal blue screen Indicates host failure How a Server Responds to Failure in the Boot LUN PathExplanations of Entries Known Issues Ntosknl BsodEMC Fibre Channel with QLogic HBAs in Windows Hosts Third-Party Software QLogic SANSurfer SANBlade Manager Veritas Volume Manager 3.x for Windows After completing these changes, reboot the host systemEMC Fibre Channel with QLogic HBAs in Windows Hosts Troubleshooting Problem Problems and SolutionsSolution EMC Primus case emc69308 Direct-connect to EMC CLARiiON EMC Support. Windows 2003 driver 8.2.2.20 and later alreadyContain this correction A host may log a message noting that disk has reached aEMC Fibre Channel with QLogic HBAs in Windows Hosts Index Index