HP D5970A - NetServer - LCII Installation And Configuration Manual page 91

Chapter 7
Although undesirable, NetWare allows you to create volumes into the virtual
space. This is because during volume creation, NetWare only looks at the
beginning of the volume and if there is real storage space there, the volume will
be created. However, when writing to this volume, you cannot write beyond the
physical limit and write errors will be generated when the physical space is filled.
Obviously you want to take care when creating volumes in a partition containing
virtual space. Use the HP NetRAID Config module to check the actual physical
capacity available, and be sure the total size of NetWare volumes do not exceed
this value.
One other useful measure is to set the capacity alarms under NetWare so that
warnings will be generated when you approach the limit of a volume.
The Online Capacity Expansion feature cannot be used if a logical drive spans
multiple arrays. Each array can contain only one logical drive. Reconstruction
(for the purposes of adding a drive to an array) can be done only on an array
having a single logical drive. It is also important to plan future storage expansion
into your installation. This ensures that you can easily expand capacity without
the need for backup/restore operations or reconfiguration.
NOTE SFT-3 and mirroring users: Novell's operating system,
which provides system level fault tolerance by mirroring two
systems, is not compatible with the Online Capacity
Expansion feature. SFT-3 mirrors disk storage on a partition
basis rather than a volume basis. Because of the virtual space
created within the partition, SFT-3 cannot successfully mirror
the partitions. This limitation also applies to regular mirroring
(without SFT-3) of volumes. SFT-3 users may add storage
capacity online without bringing the two systems down if
enough drives are added to create a new array and logical
drive on an HP NetRAID Series adapter. Under the Install
module, NetWare can then scan for new devices and detect the
new logical drive.
Preparing for Online Capacity Expansion
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