HP StorageWorks LUN Configuration and Security Manager XP user guide for the XP12000/XP10000/SVS200 (T1714-96008, June 2006)

22 Overview of LUN Manager
• ”Defining LU paths” on page 75
• ”Changing or viewing LU path settings” on page 84
• ”Defining and viewing alternate paths” on page 93
For more information about LUN configuration, see ”Overview of Volume Manager and Custom Volume
Size” on page 127.
NOTE:
• In iSCSI environments, you can define up to 1,024 LU paths for one iSCSI target and up to 1,024 LU
paths for one port.
• You cannot define LU paths to LUN On-Demand volumes.
• You cannot define LU paths to volumes reserved by Auto LUN XP.
• You can create up to 64 iSCSI targets for one Fibre Channel port.
• You cannot define LU paths to journal volumes.
• You cannot define LU paths to pool volumes.
• In iSCSI environments, you cannot define LU paths to logical volumes that do not have the Read/Write
access attribute.
• You cannot define LU paths to volumes on which a volume management area (VMA) is set.
Configuring LU paths in NAS environments
In Fibre Channel or iSCSI environments, you must classify hosts into host groups based on the platform. In
NAS environments, however, you do not need to classify hosts. In NAS environments, hosts attached to a
NAS port are automatically registered in a host group named User.
In NAS environments, LUs are classified into system LUs or user LUs. System LUs contain system
information necessary for managing the NAS environment and can be manipulated only by HP service
representatives. User LUs contain data that can be accessed by network users. When configuring NAS
systems, you must define paths between hosts and user LUs.
Figure 4 gives an example of defining paths between hosts and user LUs. In NAS environments, paths are
always defined between a user LU and a group of four ports. Because of this multi-path configuration,
hosts can access the user LU even if one of the paths fails.
NOTE:
• In NAS environments, you can define up to 256 LU paths for one NAS port.
• In NAS environments, you cannot define LU paths to logical volumes that do not have the Read/Write
or Read/Write (S-VOL Disable) access attribute.
• You cannot define LU paths to LUN On-Demand volumes.
• You cannot define LU paths to volumes reserved by Auto LUN XP.
• The LUN Manager pane displays two host groups (that is, User and NAS-Sys) below each NAS port.
When defining LU paths, you can use only User; you cannot use NAS-Sys.
• You cannot define LU paths to volumes on which a volume management area (VMA) is set.
• You cannot define LU path to journal volumes.
• You cannot define LU path to virtual volumes.