Device Mapper Multipath Enablement Kit for HP StorageWorks Disk Arrays v4.3.
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Overview This release notes discusses the recent product information about HP Device Mapper Multipath (HPDM Multipath) Enablement Kit for HP StorageWorks Disk Arrays v4.3.0. This incremental release is to provide enablement for HP StorageWorks Disk Arrays MSA2312sa, MSA2324sa, MSA2312i, MSA2324i, and to support RedHat Enterprise Linux 4 Update 8 operating system.
NOTE: The following features are available only on SLES11 operating system: • Assigning user defined priority to the path • Least pending I/O path • DM service time For details on multipathing support for SAN Boot environment, see the Booting Linux x86 and x86_64 systems from a Storage Area Network with Device Mapper Multipath document available at: http://h18006.www1.hp.com/storage/networking/bootsan.html What's new HPDM Multipath 4.3.
System feature Supported hardware and software See http://h18006.www1.hp.com/storage/networking/index.html, Host Bus Adapters (HBA) http://h18004.www1.hp.com/products/servers/proliantstorage/adapters/index.html, and SAN Switches http://h20000.www2.hp.com/bizsupport/TechSupport/DriverDownload.jsp?lang=en& cc=us&prodNameId=3628653&taskId=135&prodTypeId=332283& prodSeriesId=3628652&submit.y=2&submit.
NOTE: • For more information on configuring iSCSI parameters, see Configuring iSCSI parameters. • Device Mapper Multipath does not support coexistence with other multipath products. • Device Mapper Multipath does not support Active-Passive Storage Arrays.
Installing Device Mapper Multipath tools Ensure the following RPMs bundled with the operating system distributions are installed on the system: • For RHEL 4 Update 7: • device-mapper-1.02.25-2.el4 or later • device-mapper-multipath-0.4.5-31.el4 or later • For RHEL 4 Update 8: • device-mapper-1.02.28-2.el4 or later • device-mapper-multipath-0.4.5-35.el4 or later • For RHEL 5 Update 2: • device-mapper-1.02.24-1.el5 or later • device-mapper-multipath-0.4.7-17.
Configuring Device Mapper Multipath to enable HP arrays This section describes the following: • Recommended device parameter values • Setting up HPDM Multipath • SAN configuration supported by DM Multipath Recommended device parameter values To enable HP arrays, edit /etc/multipath.
device { vendor product getuid_callout prio_callout hardware_handler path_selector path_grouping_policy failback rr_weight no_path_retry rr_min_io path_checker "HP" "MSA VOLUME" "/sbin/scsi_id -g -u —s /block/%n" "/sbin/mpath_prio_alua /dev/%n" "0" "round-robin 0" group_by_prio immediate uniform 18 100 tur } For MSA2012sa/MSA2312sa/MSA2324sa device { vendor product getuid_callout prio_callout hardware_handler path_selector path_grouping_policy failback rr_weight no_path_retry rr_min_io path_checker "HP"
For MSA2312fc/MSA2324fc/MSA2312i/MSA2324i device { vendor product getuid_callout hardware_handler path_selector prio_callout path_grouping_policy failback rr_weight no_path_retry rr_min_io path_checker } 10 "HP" "MSA2312fc|MSA2324fc|MSA2312i|MSA2324i" "/sbin/scsi_id -g -u -s /block/%n" "0" "round-robin 0" "/sbin/mpath_prio_alua /dev/%n" group_by_prio immediate uniform 18 100 tur
NOTE: • For SLES 11, in the device section, replace getuid_callout “/sbin/scsi_id —g —u —s /block/%n” with getuid_callout “/lib/udev/scsi_id —g —u /dev/%n” • For SLES 10 SP2, in the device section for MSA2012sa, MSA2312sa, and MSA2324sa, replace getuid_callout “/sbin/hp_scsi_id —g —u —n —s /block/%n” with getuid_callout “/sbin/scsi_id —g —u —n —s /block/%n” • For SLES 10 SP2/SLES11, in the device section, replace prio_callout “/sbin/mpath_prio_alua %n” with prio alua • In XP arrays, there are di
Configuring QLogic HBA parameters To configure the QLogic HBA parameters for QLogic 2xxx family of HBAs, complete the following steps: 1. Edit the /etc/modprobe.conf file in RHEL hosts and /etc/modprobe.conf.
#mv /boot/initrd-.img /boot/initrd-.img.old b. Make a new initrd image by executing the following command: • For SLES 11: #mkinitrd -k —i • For other operating systems: #mkinitrd /boot/initrd-.img `uname -r` c. Edit the value for default parameter in /boot/grub/menu.lst file to boot with the new initrd image. • For other operating systems using the HP Emulex drivers, execute the following command: /opt/hp/hp-lpfc/make_initrd 3. Reboot the host.
c. Edit the value for default parameter in /boot/grub/menu.lst file to boot with the new initrd image. SAN configuration supported by DM Multipath Table 2 lists the maximum SAN configuration supported by DM Multipath.
Known issues Following are the known issues in the HPDM Multipath 4.3.0 release: • multipath commands may take longer time to execute on heavily loaded servers or under path failure conditions. • Blacklisting the multipath device in the /etc/multipath.conf file and restarting the multipath service may not remove the device on RHEL 4 distributions.
