HP NetRAID 1 Controller - Manual (Page 15)

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Without Reboot
You can only add capacity as a new volume. You will need to add enough physical drives to create
a new array and logical drive using NetRAID Config. Then under NetWare Install, you will need to
“Scan For New Devices”, and configure the new logical drive as a new NetWare volume.
With Reboot
If a reboot is acceptable, then the server can be downed, and Virtual Sizing enabled in Express
Tools. This assumes that you have not yet used the logical drive so that the 80 gigabyte partition can
be created. If the logical drive has already been partitioned and used, to enable volume expansion,
you will need to save data, enable Virtual Sizing, then repartition the drive and restore the data.
Now that volume can be expanded on-line whenever required.
F. Online Capacity Expansion Feature under Microsoft
Windows-NT
This section describes how users can take advantage of the NetRAID On-line Capacity Expansion
feature under the Microsoft NT operating system. The benefit for the user is that new storage
capacity can be added to the HP NetRAID and HP NetRAID-1 adapters and can be put on-line for
use without rebooting the server. Follow the steps outlined below to prepare a system for capacity
expansion and then add a volume. This will provide the user with an easy process to add storage
whenever needed.
Theory of Operation
Normally when a logical drive is created on the HP NetRAID or HP NetRAID-1 adapters, it presents
this logical drive to the operating system as configured. The drawback is that operating systems do
not support expansion of a logical drive where the partition and physical capacity are the same size.
Adding capacity requires downing server to reconfigure/restore an existing volume or adding the
new storage space as a new volume. Using the Capacity Expansion feature allows you to add a
volume without downing the server.
Capacity Expansion is enabled on a per-logical drive basis. When enabled, the controller presents to
the operating system a logical drive of 80 gigabytes. However, only a part of the 80 gigabyte logical
drive exists as actual physical storage. You configure volumes to only use the actual physical space
while the virtual space allows room for on-line expansion. For example, assume you have 1 logical
RAID-5 drive built from 4 physical hard disk drives of 9 gigabytes each; the result is 27 gigabytes of
actual storage space. If you enable Virtual Sizing for this logical drive, then the OS will see a
logical drive of 80 gigabytes, but the first 27 gigabytes are real while the last 53 gigabytes are
virtual. Since there is unused logical drive space, the physical storage of 27 gigabytes can be
expanded on-line, but the total logical drive remains at 80 gigabytes.
Precautions
When using the Capacity Expansion feature, it is important to not create volumes which exceed the
actual physical capacity. If you attempt to do this under NT, the format operation will fail. If you
extend an existing partition into virtual space, this will be detected upon rebooting. In either case, be
sure to use no more than the actual available physical capacity. Capacity of the logical drive can be
checked with the NetRAID Assistant under NT.
Setting Up Your Array for Capacity Expansion (OS on non-disk array drive)
When using capacity expansion, you should use a single logical drive since capacity expansion is
controlled on a per logical drive basis. Reconstruction (e.g., adding a drive to an existing array) can
only be done on an array having a single logical drive. It is also important to plan future storage