Online Capacity Expansion Under Novell Netware; Theory Of Operation - HP D5970A - NetServer - LCII Configuration Manual

Chapter 7
This chapter is divided into two sections:
See "Capacity Expansion Under Novell NetWare" if you are using Novell
NetWare.
See "Capacity Expansion Under Windows NT" if you are using Microsoft
Windows NT.

Online Capacity Expansion Under Novell NetWare

Theory of Operation

Normally, to add capacity you must shut down the server to reconfigure and then
restore data, or you must add the new storage space as a new volume. The Online
Capacity Expansion feature allows you to expand an existing logical drive
without shutting down the server.
Capacity expansion is enabled separately on each logical drive. When enabled,
the controller presents to the operating system a logical drive of 144 GB.
However, only a part of the 144-gigabyte logical drive exists as actual physical
storage. You configure volumes to use only the actual physical space while the
virtual space allows room for online expansion.
For example, assume you have one RAID-5 logical drive built from four physical
hard disk drives of 9 GB each. The result is 27 GB of actual storage space. If you
enable Virtual Sizing for this logical drive, then the operating system will see a
logical drive of 144 GB. Only the first 27 GB are real, 9 GB are used for parity,
and the last 108 GB are virtual. Under NetWare, you create an 144-GB partition,
but within that partition you only create a logical drive totaling 27 GB or less.
Since there is unused partition space, the physical storage of 27 GB can be
expanded online by adding another hard disk drive, but the partition remains at
144 GB.
Precautions
When using the Online Capacity Expansion feature, it is very important that you
do not create volumes that exceed the actual physical capacity. You must add up
the capacities of all volumes that may be using the physical storage space, such as
a DOS volume, SYS volume, Hot Fix Area, and any user volumes. This is most
important if NetWare will be installed on the disk array (rather than a SCSI disk
outside of the HP NetRAID system). During installation, if the total physical
capacity is exceeded during volume creation, a NetWare abend and loss of the
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Preparing for Online Capacity Expansion