HP XP P9500 Storage - Manual (Page 59)

4 Configuring expanded LU provisioning
Configuring expanded LU provisioning involves combining several smaller LDEVs into an expanded
logical unit volume to make a LUSE (logical unit size expansion) volume that is larger than the
standard 2.8 TB. A LUSE volume is a set of LDEVs defined to one or more hosts as a single data
storage unit. A LUSE volume is a concatenation of two to 36 LDEVs (up to 60-TB limit) that are
presented to a host as a single LU.
This provisioning strategy is for use on open systems. LUN Expansion software is required to use
the LUSE feature to configure expanded LU provisioning.
About LUSE
The LUSE feature is for open-system logical volumes and allows you to configure one large logical
volume by combining several smaller LDEVs. To use this feature, you need the software called
Open Volume Management, which includes LUN Expansion software.
The LUSE feature allows hosts that can use only a limited number of LUs per fibre interface to have
access to larger amounts of data by using expanded LUs. To create an open-systems volume (LU)
larger than 2.8 TB, you must use the LUSE feature to combine open-systems volumes.
Up to 36 LDEVs can be combined to create one large logical volume, called a LUSE volume. The
ID of the logical volume defined as the large logical volume is represented by the smallest LDEV
ID (assigned to the top LDEV). The host recognizes the expanded logical volume as one
representative LDEV. As long as the number of LDEVs combined into one large logical volume does
not exceed 36, you can arbitrarily select any LDEVs as the volumes to combine, regardless of their
size (or capacity) or whether they are on the same control unit (CU).
Using the LUSE feature, you can also combine several LDEVs and a LUSE volume (combined LDEVs)
into one LUSE volume, or combine LUSE volumes together into one LUSE volume. The host also
recognizes this type of LUSE volume as one LDEV.
The host cannot access the individual LDEVs or LUSE volumes that make up an expanded LU (LUSE
volume). If you want to access the individual volumes, you must release the expanded LU.
For information about the maximum LU capacity supported by your operating system, contact the
vendor of your operating system.
LUN Expansion license requirements
Use of LUN Expansion on the P9500 storage system requires license key on the Remote Web
Console computer for Open Volume Management software. For details about the license key or
product installation, see the HP P9000 Remote Web Console User Guide.
Supported operating systems
Whether hosts can access a volume larger than 2 TB depends on the operating systems of the
hosts. Hosts running the following operating systems can access LUSE volumes larger than 2 TB.
•
AIX 5.2 TL08 or later
•
AIX 5.3 TL04 or later
•
Windows Server 2003 SP1 or later
•
Red Hat Enterprise Linux AS 4 Update 1 or later
Other operating systems do not support accessing LUs larger than 2 TB. If hosts use other operating
systems, make sure that LUs are not larger than 2 TB.
About LUSE 59