HP StorageWorks Enterprise Virtual Array Online Firmware Upgrade Best Practices (5697-6388, January 2007)

2 Evaluating the SAN for an online

upgrade

Before performing an online upgrade, the SAN environment must be evaluated to determine system

timeouts, identify I/O patterns, and select the best time to perform the upgrade. This will help ensure the

success of the online upgrade.

Managing host I/O timeouts

The default values for host operating parameters such as LUN timeout and queue dep th are typically set

to values that ensure proper operation with the storage system. These values are appropriate for most

storage system operations, including online ﬁrmware upgrades. In general, host LUN timeouts of 60

seconds or m

ore are adequate to accommodate an online upgrade. In most situations it will not be

necessary

to alter these settings to perform an online ﬁrmware upgrade.

If any host

timeout values have been decr eased to less than 60 seconds, it will be necessary to reset

them to their original default value. The following section provide a summ ary of the steps and com m ands

involve d in checking and changing timeout values for each supported operating system. Refer to the

operating system documentation for more information.

NOTE:

• All opera

ting systems are supported for online controller ﬁrmware upgrades when the following

guideli

nes are followed for both raw and ﬁle system devices.

• Unless otherwise indicated, cluster testing has not yet been completed in combination with online

controller ﬁrmware upg rades. Cluster information will be added to this document when the testing is

complete.

Microsoft Windows

NOTE:

• Ensure that MPIO is installed and both paths are active and have access to the array.

• Boot devices are supported with online controller ﬁrmware upgrades.

Checking timeout values

• The key timeout setting is in the registry at HKEY_LOCAL_MACHINE/SYSTEM/

CurrentControlSet/Services/Disk/TimeoutValue is set to 3c (60 seconds)

HP-U

CAUTION:

If Serviceguard is being used, the timeout value is 45 s econds.

HP StorageWorks Enterprise Virtual Array online ﬁrmware upgrade best practices