Configuring User-Friendly Names In The /Etc/Multipath.conf File - Novell LINUX ENTERPRISE SERVER 10 - STORAGE ADMINISTRATION GUIDE FOR EVMS Administration Manual

The devices should now be listed in /dev/disk/by-id, and have symbolic links to
their Device Mapper device names. For example:
lrwxrwxrwx 1 root root 10 Jun 15 09:36 scsi-mpath1 -> ../../dm-1
6 Restart the boot.md service and the RAID device by entering
/etc/init.d/boot.md start
7 Check the status of the software RAID by entering
mdadm --detail /dev/md0
The RAID's component devices should match their Device Mapper device names that are listed
as the symbolic links of devices in the /dev/disk/by-id directory.
8 Make a new initrd to ensure that the Device Mapper multipath services are loaded
before the md RAID services on reboot. Enter
mkinitrd -f mpath
9 Reboot the server to apply these post-install configuration settings.
10 Verify that the software RAID array comes up properly on top of the multipathed devices by
checking the RAID status. Enter
mdadm --detail /dev/md0
For example:
Number Major
0 253
1 253
2 253
5.9 Configuring User-Friendly Names in the /etc/
multipath.conf File
The default name used in multipathing is the UUID of the logical unit as found in the /dev/disk/
by-id directory. You can optionally override this behavior with user-friendly names instead. User-
friendly names can be set via the ALIAS directive in the multipath.conf file.
IMPORTANT: We recommend that you do not use aliases for the root device as the ability to
seamlessly switch off multipathing via the kernel command line is lost because the device names
differ.
For an example of multipath.conf settings, see the /usr/share/doc/packages/
multipath-tools/multipath.conf.synthetic file.
1 In a terminal console, log in as the root user.
2 Enter the following command (all on one line, of course):
cp /usr/share/doc/packages/multipath-tools/
multipath.conf.synthetic /etc/multipath.conf
3 Open the /etc/multipath.conf file in a text editor.
4 Uncomment the Defaults directive and its ending bracket.
5 Uncomment the user_friendly_names option, then change its value from No to Yes.
6 Specify names for devices using the ALIAS directive.
Minor RaidDevice
0 0
1 1
2 2
State
active sync /dev/dm-0
active sync /dev/dm-1
active sync /dev/dm-2
Managing Multipath I/O for Devices 49