HP StorageWorks Clustered File System 3.6.1 Windows Storage Server Edition administration guide (AG515 - 96007, August 2008)

Chapter 20: SAN Maintenance 286
Remove the comment character (#) at the beginning of the line and set the
psd_timeout value to 180:
psd_timeout 180
Restart the Nodes
After changing the timeouts on all nodes, stop and restart HP Clustered
File System on each node. The stop/restart can be performed on one node
at a time.
After the Storage Capacity Upgrade
When the disk upgrade is complete, restore the original scl.conf file and
remove the registry value that you added. After this changes are made on
all nodes, stop and restart HP Clustered File System on each node. The
stop/restart can be performed on one node at a time.
Caveat
Increasing the timeouts allows the array to complete its data rebalancing
operations. However, the performance of the running cluster will be
impacted. For example, in an I/O of a 4K block takes one minute, it is
possible that all users will be serialized behind this cluster-wide blocking
I/O. This is more likely when creating files than with a read-only
workload. For this reason, HP recommends that you insert/replace new
drives at times of lower user workload.
Online Replacement of a FibreChannel
Switch
This procedure applies only to sites using EMC PowerPath.
When a cluster includes multiple FibreChannel switches, you can replace
a switch without affecting normal cluster operations. The following
conditions must be met when performing online replacement of a
FibreChannel switch.
• The replacement switch must be the same model as the original switch
and must have the same number of ports.
• HP Clustered File System must be stopped on any servers that are
connected only to the switch to be replaced.