儲存-配置多路徑

Multipath

多路徑軟體作用：

1）冗餘.為了保證儲存訪問的可靠性,一般至少需要用2塊光纖卡,透過2個FC switch,接在磁碟陣列的兩個控制器上.當一條路徑出現問題,還有另一條路徑可以訪問.

2）負載均衡.既然有2個path，那麼如果某一個path只是備用就浪費了.所以MultiPathing的軟體的另一個功能就是load balance（也稱為Active/Active）.但這個功能不僅僅由MultiPathing軟體實現，磁碟陣列本身也必需支援，否則，MultiPathing只能實現主備方式（Active/Passive）.

建立multipath.conf文件,新增如下內容：

# This is a basic configuration file with some examples, for device mapper
# multipath.
# For a complete list of the default configuration values, see
# /usr/share/doc/device-mapper-multipath-0.4.7/multipath.conf.defaults
# For a list of configuration options with descriptions, see
# /usr/share/doc/device-mapper-multipath-0.4.7/multipath.conf.annotated

# Blacklist all devices by default. Remove this to enable multipathing
# on the default devices.
blacklist {
# devnode "*" --要註釋掉*
}

## By default, devices with vendor = "IBM" and product = "S/390.*" are
## blacklisted. To enable mulitpathing on these devies, uncomment the
## following lines.
#blacklist_exceptions {
# device {
# vendor "IBM"
# product "S/390.*"
# }
#}

## Use user friendly names, instead of using WWIDs as names.
defaults {
user_friendly_names yes
}
##
## Here is an example of how to configure some standard options.
##
#
#defaults {
# udev_dir /dev
# polling_interval 10
# selector "round-robin 0"
# path_grouping_policy multibus
# getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
# prio_callout /bin/true
# path_checker readsector0
# rr_min_io 100
# max_fds 8192
# rr_weight priorities
# failback immediate
# no_path_retry fail
# user_friendly_names yes
#}
##
## The wwid line in the following blacklist section is shown as an example
## of how to blacklist devices by wwid. The 2 devnode lines are the
## compiled in default blacklist. If you want to blacklist entire types
## of devices, such as all scsi devices, you should use a devnode line.
## However, if you want to blacklist specific devices, you should use
## a wwid line. Since there is no guarantee that a specific device will
## not change names on reboot (from /dev/sda to /dev/sdb for example)
## devnode lines are not recommended for blacklisting specific devices.
##
#blacklist {
# wwid 26353900f02796769
# devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
# devnode "^hd[a-z]"
#}
#multipaths {
# multipath {
# wwid 3600508b4000156d700012000000b0000
# alias yellow
# path_grouping_policy multibus
# path_checker readsector0
# path_selector "round-robin 0"
# failback manual
# rr_weight priorities
# no_path_retry 5
# }
# multipath {
# wwid 1DEC_____321816758474
# alias red
# }
#}
#devices {
# device {
# vendor "COMPAQ "
# product "HSV110 (C)COMPAQ"
# path_grouping_policy multibus
# getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
# path_checker readsector0
# path_selector "round-robin 0"
# hardware_handler "0"
# failback 15
# rr_weight priorities
# no_path_retry queue
# }
# device {
# vendor "COMPAQ "
# product "MSA1000 "
# path_grouping_policy multibus
# }
#}

將multipath.conf檔案放到/etc目錄下

安裝gcc包：

rpm -ivh kernel-headers-2.6.18-274.el5.x86_64.rpm
rpm -ivh glibc-headers-2.5-65.x86_64.rpm
rpm -ivh glibc-devel-2.5-65.x86_64.rpm
rpm -ivh gcc-4.1.2-51.el5.x86_64.rpm
rpm -ivh kernel-uek-devel-2.6.32-200.13.1.el5uek.x86_64.rpm

安裝HBA卡驅動：

tar -xvf brocade_driver_linux_rhel5_v3-0-0-0.tar(5.5.6.7)(oracle).gz

rpm -ivh kernel-uek-devel-2.6.32-200.13.1.el5uek.x86_64.rpm

安裝HBA卡驅動 radhat linux

./brocade_install_rhel.sh

安裝HBA卡驅動 Oraclelinux

./brocade_install.sh

啟動多路徑服務：

[root@yoon ~]# chkconfig multipathd on

[root@yoon ~]#service multipathd start