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}
Note: Edit the blacklist section for your server, using either a regular expression or
WWID to exclude the appropriate devices. Refer to the “SUSE Linux Enterprise
Server 11 SP1 Storage Administration Guide” listed in the Revision section of this
document for more information on blacklisting devices.
11) Continue the multipath software configuration on the server. Edit the ‘devices’
section of the multipath configuration file. In the default multipath configuration
file, the entire devices section is commented out.
Add the following lines for the PS Series array:
# BEGIN - PS Series device edits
devices {
device {
vendor "EQLOGIC"
product "100E-00"
path_grouping_policy multibus
features "1 queue_if_no_path"
path_checker readsector0
failback immediate
path_selector "round-robin 0"
rr_min_io 10
rr_weight priorities
}
}
# END - PS Series device edits
12) Set the multipathd daemon to automatically start at boot then start multipathd:
# chkconfig multipathd on
# service multipathd start
Starting multipathd done
13) The Linux device mapper dynamically names it’s entries (e.g. dm-3, dm-5, …). This
means that the device name for an iSCSI volume could vary across reboots, which
presents an issue for consistently mounting the filesystem. Fortunately, the
multipath subsystem provides a persistent naming scheme in which device mapper
names can be consistently associated with an iSCSI volume.
Use the multipath command to identify the persistent name for the iSCSI volume:
# multipath –ll
mpath0 (36090a0286066eebeecbf34c61892e727) dm-3 EQLOGIC,100E-00
[size=50G][features=1 queue_if_no_path][hwhandler=0][rw]
\_ round-robin 0 [prio=2][active]
\_ 19:0:0:0 sdc 8:32 [active][ready]
\_ 18:0:0:0 sdd 8:48 [active][ready]