HP XP P9500 Disk Array Configuration Guide (AV400-96496, May 2014)

Configuring disk array devices
Disks in the disk array are configured using the same procedure for configuring any new disk on
the host. This includes the following procedures:
• Changing the device parameters
• Assigning the new devices to volume groups
• Creating the Journaled File Systems
• Mounting and verifying the file systems
Creating scripts to configure all devices at once can save you considerable time.
Changing the device parameters
When the device files are created, the system sets the device parameters to the system default
values. You might need to change a few of those values for each new OPEN-x device: For more
information, see Table 24 (page 89) and Table 25 (page 89).
• Read/write (R/W) timeout value
• Queue depth
• Queue type
Table 24 Device parameters-read/write timeout and queue type (IBM AIX)
Required ValueDefault ValueParameter
6030Read/write timeout
SimpleNoneQueue type
Table 25 Device parameters-queue depth (IBM AIX)
Recommended ValueParameter
32
Queue depth per LU
1024
Queue depth per port (MAXTAGS)
The recommended queue depth settings might not provide the best I/O performance for your
system. You can adjust the queue depth setting to optimize the I/O performance of the disk array.
Displaying the device parameters using the AIX command line
At the command line prompt, enter lsattr -E -l hdiskx, where hdiskx is the device file
name.
Example
# lsattr –E -l hdisk2
Changing the device parameters using the AIX command line
1. To change the R/W timeout parameter, enter:
chdev –1 hdiskx –a rw_timeout='60'
2. To change the queue depth parameter, enter:
chdev –l hdiskx –a queue_depth='x'
where x is a value from the previous table.
3. To change the queue type parameter, enter:
chdev –l hdiskx –a q_type='simple'
Configuring disk array devices 89