Red Hat CLUSTER SUITE - CONFIGURING AND MANAGING A CLUSTER 2006 Manual page 177

Multipath-usage.txt
Appendix C.
Update 3
For some conditions, that may not be sufficient. If DM-MP is
multipathing devices that you do not want it to work on, you can
blacklist the devices by either device name or WWID.
NOTE: It is safest to blacklist individual devices by WWID, because
their device names may change.
Several other configuration options are detailed later in this
document. To check the
do a dry run with the following command:
# multipath -v2 -d
3. Set the multipathd init script to run at boot time. by issuing
the commands
# chkconfig --add multipathd
# chkconfig multipathd on
4. start dm-multipath (This is only necessary the first time.
reboot, this should happen automatically).
# multipath
# /etc/init.d/multipathd start
After initial setup, all access to the multipathed storage should go
through the multipath device.
Configuration File:
Many features of DM-MP are configurable using the configuration file,
/etc/multipath.conf.
For a complete list of all options with descriptions, refer to
/usr/share/doc/device-mapper-multipathd-0.4.5/multipath.conf.annotated
The configuration file is divided into four sections: system defaults,
blacklisted devices (devnode_blacklist), per storage array model settings
(devices), and per multipath device settings (multipaths).
multipath device settings are used for the multipath device with a
matching "wwid" value. The per storage array model settings are used
for all multipath devices with matching "vendor" and "product" values.
To determine the attributes of a multipath device, first the per
multipath settings are checked, then the per controller settings, then
the system defaults.
setup step 2.
NOTE: There are compiled-in defaults for the "defaults",
File for Red Hat Enterprise Linux 4
effects of configuration changes, you can
The blacklisted device section is described
161
On
The per