
Continue with the change in id mappings (y/n) [n] ?
y
Change in Target id mappings has been performed
#
4.7 Verifying the Fibre Channel Device Configuration
After you have synchronized the target ID mapping across cluster members,
verify that the Fibre Channel storage has been correctly configured. The
following are some suggested methods:
•
Use the
emxmgr -t
utility on each member system to display the Fibre
Channel topology and compare the displays.
•
Use the
scu
utility to examine various targets and LUNs to verify that
the newly generated kernel has brought the Fibre Channel storage on
line as expected. For example:
#
scu
scu>
scan edt
scu>
show edt
Ctrl/D
•
Use the
uerf
or
dia
utility to verify the device configuration by
displaying the startup messages in reverse order (so that the most recent
messages are displayed first):
#
dia -R -i osf=300 | more
•
Use the
dd
command to generate some I/O activity by reading from the
Fibre Channel disks. Visually verify that the correct disk or set of disks
is active. For example:
#
dd if=/dev/rrzb49c of=/dev/null
4.8 Determining the Device Special File Name for a Disk
The actual device number of a particular disk will be determined both by:
•
The SCSI target assigned by the method discussed in Section 4.6
•
The bus number assignment as determined (in the traditional manner)
by the system configuration file.
Using the cluster’s SCSI bus assignments, the data that is recorded in the
/etc/emx.info
, and the list of Fibre Channel worldwide names that you
compiled in Section 4.4, you can derive a device’s special file name as follows:
(SCSI bus # for the emx instance) * 8 +
(target id # for the HSG80 controller on the emx instance),
prefixed by the lun value
("" for lun 0, "b" = lun 1, "c" lun 2, etc).
Installing Fibre Channel Hardware and Configuring the emx Driver 4–25