User manual HP STORAGEWORKS B-REMOTE REPLICATION SOLUTIONS STORAGEWORKS BOOTING ITANIUM LINUX SYSTEMS FROM A STORAGE AREA NETWORK APPLICAT

[. . . ] HP StorageWorks Booting Itanium Linux systems from a storage area network application notes Part number: AA-RV29H-TE Eighth edition: August 2007 Legal and notice information © Copyright 2002, 2007 Hewlett-Packard Development Company, L. P. © Copyright 2007 Emulex Corporation © Copyright 2007 QLogic Corporation Hewlett-Packard Company makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Hewlett-Packard shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material. This document contains proprietary information, which is protected by copyright. [. . . ] (This is the LUN to which your boot device has access. ) Press Enter again to return to the menu. The boot table displays an entry listing for the boot device target WWN and LUN information. Continue pressing Esc to exit the utility and return to the shell prompt. Restrictions This section describes boot from SAN restrictions. 10 Installing in single-path mode HP recommends that you initially deploy the operating system to the SAN in single-path mode. To do so, map the root directory (/) and /boot directory to /dev/sda (or to the first Fibre Channel device). After deploying the operating system to the SAN, install the supported failover driver, and then configure multiple paths. Assigning the primary boot HBA For boot from SAN configurations, HP recommends placing the primary boot HBA in PCI slot number 1, or in the next available PCI slot. To ensure correct LUN discovery, the primary boot HBA must be before all other HBAs on the PCI bus. Active/Passive paths and boot LUNs In boot from SAN configurations, the boot paths must be on the active path to the boot LUN. In the event of a failover, storage controller reboot, or some other event in the SAN, it is possible for a currently configured boot path to become the standby path to the LUN. In this case, attempting to boot using the configured boot path fails. To correct this problem, either configure a new boot option at the EFI level using the second path to the LUN, or switch the standby path to the boot LUN back to the active path. CAUTION: If there are other servers attached to the MSA storage array, stop all I/O on those servers before switching paths. Allow the array to stabilize before restarting I/O. Target ports When the primary boot path fails and the host is rebooted, the host may fail to find the boot LUN through the alternate path if the order of target ports (as seen by the HBAs) is not consistent across SANs. Proper configuration ensures that if the primary path fails during a host reboot, proper failover occurs, and the secondary path functions as the boot path, as expected. You must arrange the target ports on the SAN so that all SANs have the same target port order. Emulex HBA's support a maximum of up to ten target ports. NOTE: When arranging target ports on the SAN, you must ensure that the connections do not move at a later time. This can limit the flexibility for connecting targets on the SAN (see Using the Udev utility with SUSE Linux systems). New storage LUNs If new storage LUNs are presented to the server between reboots, the boot from SAN attempt may fail. The Linux kernel maps LUNs in the order of discovery. If the relative position of the boot LUN has changed, the boot attempt may fail. For SUSE Linux systems, HP recommends using the udev utility to prevent an unsuccessful boot, as described in "Using the Udev utility with SUSE Linux systems" on page 12. NOTE: If you create a new EFI boot option, you must edit the /etc/fstab file to mount the correct boot, root, and swap partitions. HP StorageWorks Booting Itanium Linux systems from a storage area network application notes 11 For RHEL Linux systems There are no known restrictions at this time. Boot from SAN configurations using HP A8002A HBA You may experience problems changing HBA settings after upgrading to firmware version 2. 70a5. A workaround for this problem is to revert back to firmware version 2. 50a6. Boot from SAN configurations using RHEL 4 Update 4 and AB379A or AB429A HBAs If the RHEL installation program displays an error message indicating "no disk found" for installation, the HBA driver may need to be manually loaded for the boot from SAN installation to succeed. At the ELILO prompt, enter:linux askmethod nostorage. [. . . ] Reboot the system. Working with the A6826A HBA This section describes how to upgrade and configure the A6826A HBA for booting from a SAN. A6826A HBA revision restrictions The following A6826A HBA revision restrictions apply: · The A6826A HBA, MFR revision D or later, is supported for Linux boot from SAN configurations. · The A6826A HBA, MFR revision B, does not include an EFI driver in flash memory and does not support booting from a SAN as shipped. However, you can upgrade the software to support booting from a SAN as described in "Upgrading the A6826A HBA for booting from a SAN" on page 15. 14 Upgrading the A6826A HBA for booting from a SAN To enable booting from a SAN, the A6826A HBA must include an EFI HBA driver. To upgrade early versions of the A6826A HBA with this driver: 1. [. . . ]