User`s guide

Multipathing Considerations
Before you change multipathing conguration note the following considerations. Then follow
the instructions for your machine architecture (SPARC or x86) described in the subsequent
sections. Some devices need to be properly congured to work with the multipathing software.
Refer to your storage array documentation for details on the device specic conguration for
your device.
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Device Specic Considerations
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Device Name Change Considerations
In the /dev and /devices trees, multipath-enabled devices receive new names that indicate that
they are under multipath control. A device therefore will have a dierent name from its original
name when it is under multipath control.
Device name with multipath disabled:
/dev/dsk/c1t1d0s0
Device name with multipath enabled:
/dev/dsk/c0t60003BA27D5170003E5D2A7A0007F3D2d0s0
Therefore, applications that use device names directly must be congured to use the new names
whenever you change multipath conguration from disabled to enabled or vice-versa.
The system’s /etc/vfstab le and the dump conguration also contain references to device
names. On both SPARC and x86/x64-based systems the stmsboot(1m) command described in
the following sections automatically updates the /etc/vfstab le dump conguration with the
new device names. If you have application-dependent le systems which are not listed in the le
/etc/vfstab, you can use the stmsboot command to determine the mapping between the old
and new device paths.
Caution – if you have run devfsadm -C or performed a reconguration reboot then the old
device paths will not exist and the stmsboot -L command will fail to provide this information.
Enabling and Disabling Multipathing
With the release of the Solaris 10 Update 4 OS, the stmsboot(1m) command is now available for
use on SPARC, x86, and x64 based systems to enable or disable multipathing for Fibre Channel
(FC) and SAS devices. The stmsboot command updates the /etc/vfstab le and dump
conguration to reect device name changes during the next reboot. You do not need to
manually edit the /kernel/drv/fp.conf or /kernel/drv/mpt.conf les.
Multipathing Considerations
Solaris SAN Conguration and Multipathing Guide • April 200942