[summary single_path]
These multipath devices provide a single path only: &single_device_summ;

[explanation single_path]
In Linux, separate paths to the same physical device appear as separate
devices. The Linux multipath tools aggregate such devices into a single
multipath device. Through a correctly configured multipath setup, a Linux
instance has two or more independent connections to the same storage device.
This path redundancy can be used for load balancing and to maintain
availability if one of the paths fails. Multipath setups with only a single
path cannot achieve either of these goals.

To investigate your multipath configuration, use "multipath -ll".

The following multitpath devices are configured with only a single path:

&single;
[solution single_path]
Take these actions to investigate your multipath devices:

1. List your storage devices to ensure that Linux has registered
   each expected path.

   For example, use "lszfcp -D" to list your SCSI devices.

   The command output consists of lines of the form

   #<device_bus_id>/<wwpn>/<hex_lun> <h>:<c>:<id>:<d_lun>

   where each line represents a path to a storage device.
   Each line has two representations for the LUN of the storage device,
   <hex_lun> is the hexadecimal format of the LUN and <d_lun> is a decimal
   representation.

   Lines that represent paths to the same storage device have both identical
   values for <hex_lun> and identical values for <d_lun>.

   If not all expected paths are shown, ensure that all hardware components are
   in place and set up to provide multiple paths for your multipath devices.

2. If multiple paths are available, ensure that the multipath configuration
   file groups these paths correctly. In particular, ensure that the missing
   paths are not blacklisted. See the documentation that is provided with your
   distribution for details of this configuration file.

3. Restart the multipath daemon, for example, by issuing:
   ## /etc/init.d/multipathd restart

[reference single_path]
See the documentation that is provided with your distribution for more
specific information about multipathing.
Also see the man pages for the "multipath", "lsdasd", and "lszfcp" commands.
