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Note: the string highlighted in RED text is the WWID, a unique identifier and
persistent name for this volume,
14) Edit the ‘multipaths’ section of the /etc/multipath.conf file to associate this WWID
with a more user friendly name for this volume. Add these lines to your multipath
configuration file, immediately after the ‘devices’ section that was added earlier. Of
course, use the WWID for your iSCSI volume:
multipaths {
multipath {
wwid 36090a0286066eebeecbf34c61892e727
alias mpio
}
}
Note: These lines will cause the device-mapper to consistently name the volume
‘mpio, or more specifically ‘/dev/mapper/mpio’. This functionality requires that
device mapper ‘user friendly names’ are enabled in the defaults section of the
multipath.conf file. This is the default setting but you should confirm it by looking
for the following setting in the multipath.conf file:
## Use user friendly names, instead of using WWIDs as names.
defaults {
user_friendly_names yes
}
15) In order to make the multipath daemon recognize these configuration file changes,
use the ‘service reload’ command:
# service multipathd restart
Shutting down multipathd: done
Starting multipathd done
16) Run the ‘multipath –ll’ command and verify the persistent name entry in the
/dev/mapper directory:
# multipath -ll
36090a0286066eebeecbf34c61892e727: rename mpath0 to mpio
: mpio (36090a0286066eebeecbf34c61892e727) EQLOGIC,100E-00
[size=50G][features=1 queue_if_no_path][hwhandler=0][n/a]
\_ round-robin 0 [prio=2][undef]
\_ 19:0:0:0 sdc 8:32 [active][ready]
\_ 18:0:0:0 sdd 8:48 [active][ready]
# ls -l /dev/mapper
total 0