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

Chapter 20: SAN Maintenance 284
Also consult your FC switch documentation or the FC switch vendor. If
the switch appears to be operating properly, contact HP Support.
Storage
Online Insertion of New Storage
HP Clustered File System supports online insertion (OLI) of new storage,
provided that OLI support is present for your combination of storage
device, SAN fabric, HBA vendor-supplied device driver, and the
associated HBA vendor-supplied libhbaapi. (Check with your vendors to
determine whether OLI is supported.)
NOTE: OLI of new storage can cause an interruption of normal
operations on your storage device. Because of this, it is
recommended that OLI of new storage be scheduled for off-peak
hours.
When the appropriate lower-level OLI support is in place, inserting a new
disk will cause a new device to automatically become eligible for
importing. The disk can be imported with the Management Console or
mx utility, and can be used normally from that point forward.
If OLI is not possible with your hardware combination, you will need to
reboot the servers after inserting a new disk. The disk will then be visible
to the cluster.
Recommendations for Storage Capacity Upgrades
When the drives in a storage array such as the HP Storageworks EVA are
being replaced to increase capacity, the array rebalances the data as each
drive is replaced. This activity can impact the performance of the active
cluster, as the latent I/Os generated by the data rebalancing can trigger
HP Clustered File System timeouts.
When planning a disk upgrade process, in addition to following the best
practices recommended for your particular array, you should also
consider increasing the following HP Clustered File System timeouts.