HP VMA SAN Gateway Installation and Configuration Guide For release G5.5.1

64 HP VMA SAN Gateway Installation and Configuration Guide AM456-9025A
same, regardless of the number of paths that are associated with the LUN. Using the LUN serial
number, DM Multipath can determine how many paths are associated with that particular LUN. The
mechanism for getting a serial number is controlled by
getuid_callout parameter, which is
described in the next section.
Multipath Setup
This section covers setting up and configuring DM Multipath on the client side for use with HP
VMA SAN Gateway provided LUNs.
Prerequisites
Before you begin setting up DM Multipath, do the following:
1. Verify that the device-mapper-multipath rpm is installed, as shown in the following
example.
Note: The name of the package and the version shown may vary depending on your Linux
distribution and version.
2. Make a copy of the original multipath.conf file. This ensures that you have the original
file as backup, should an unexpected problem arise.
Note: The multipath package includes a file showing the default values that you can also use as a
customization template, as well as a couple of other helpful files. Go to the
/usr/share/doc/device-mapper-multipath-0.4.7/ directory to access these files:
•
multipath.conf.defaults
• multipath.conf.annotated
• multipath.conf.synthetic
Also see the man page for details on the available multipath.conf options.
[root@redhat123 ~]# rpm -qa | grep multipath
device-mapper-multipath-0.4.7-23.el5_3.1
cp multipath.conf multipath.conf.bak
man multipath.conf