here is the output of multipath.conf output..
~]# more /etc/multipath.conf
# 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 "*"
#}
## 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
polling_interval 30
failback immediate
no_path_retry 5
path_checker tur
rr_min_io 100
}
##
## 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
# }
#}
devices {
device {
vendor "IBM"
product "2107900"
path_grouping_policy group_by_serial
}
}
###################################################################
multipaths {
multipath {
wwid 36005076309ffc2000000000000000108
alias OLR_1
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 36005076309ffc200000000000000002d
alias VOT_1
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 36005076309ffc200000000000000002e
alias VOT_2
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 36005076309ffc200000000000000002f
alias VOT_3
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 36005076309ffc2000000000000000030
alias VOT_4
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 36005076309ffc2000000000000000047
alias ARCH_1
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5
}
multipath {
wwid 36005076309ffc200000000000000013c
alias BKP_1
path_grouping_policy group_by_serial
path_checker tur
path_selector "round-robin 0"
failback immediate
rr_weight priorities
no_path_retry 5