SVS200 (T1714-96008, June 2006)

20 Overview of LUN Manager

• ”Defining and viewing alternate paths” on page 93.

NOTE:

• In Fibre Channel environments, you can define up to 1,024 LU paths for one host group 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 255 host groups for one Fibre Channel port.

• You cannot define LU paths to journal volumes.

• You cannot define LU paths to pool volumes.

Configuring LU paths in iSCSI environments

After open-system hosts and the array are physically connected by cables, hubs, and so on, you must use

LUN Manager to establish I/O paths between the hosts and logical volumes. This defines which host can

access which logical volume. Logical volumes that open-system hosts can access are referred to as logical

units (LUs). Paths between open-system hosts and LUs are referred to as LU paths.

Before defining LU paths, you must classify server hosts by iSCSI targets. For example, if Linux and

Windows hosts are connected to the array, you must create one iSCSI target for Linux hosts and another

iSCSI target for Windows hosts. Then you must register the host bus adapters for Linux hosts in the Linux

iSCSI target. You must also register the host bus adapters for Windows hosts in the Windows iSCSI

target.

iSCSI targets can contain only hosts connected to the same port, and cannot contain hosts connected to

different ports. For example, if two Windows hosts are connected to port 1A and three Windows hosts

are connected to port 1B, you cannot register all five Windows hosts in one iSCSI target. You must

in another iSCSI target.