Chapter 18. Boot from SAN 221 Reduce overall cost of serversLocating server boot images on external SAN storage eliminates the need for a local diskin the server. This configuration helps lower costs and allows SAN boot users to purchaseservers at a reduced cost while still maintaining the same functionality. In addition, SANboot minimizes the IT costs through consolidation, which reduces the use of electricity andfloor space, and through more efficient centralized management.18.2 Configure SAN boot for IBM System x serversThis section provides the configuration steps for System x series server SAN boot fromN series.18.2.1 Configuration limits and preferred configurationsThe following are the configuration limits and preferred configurations for SAN boot: For Windows and Linux-based operating systems, the boot LUN must be assigned as LUN0 (zero) when doing storage partitioning. Enable the BIOS on only one HBA. Enable the BIOS on the second HBA only if you mustreboot the server while the original HBA is used for booting purposes. This configurationcan also be used if the cable or the Fibre Channel switch fails. In this scenario, use QLogicFast!UTIL or Emulex HBAnyware to select the active HBA. Then enable the BIOS, scanthe BUS to discover the boot LUN, and assign the worldwide port name (WWPN) and LUNID to the active HBA. However, when both HBA connections are functional, only one canhave its BIOS enabled. During the installation of the operating system, have only one path active at a time. Nomultipathing software is available during the installation of the operating system. Thesecond or alternate path can be activated after the installation of the operating system iscomplete. You must configure your SAN zoning or remove (disconnect) the HBA cables toleave only one path active. This implementation does not make any testing statements about supportedconfigurations. Always see the IBM System Storage N series interoperability matrix for FCand iSCSI SAN, available at:http://www.ibm.com/systems/storage/network/interophome.html In addition, review the supported configuration for your server and operating system.The infrastructure and equipment used in the examples consists of the hardware andsoftware listed in Table 18-1.Table 18-1 Hardware and software configurationServer OperatingsystemHBA model N series Data ONTAPversionIBM Systemx3655 (7985)Windows 2003Enterprise SP2QLOGICQLE2462N series 5500(2865-A20)7.3Windows 2008Enterprise ServerQLOGICQLE2462N series 5500(2865-A20)7.3
