Hitachi Dynamic Link Manager Software Users Guide for Linux

System Configuration Using an IP-SAN
In an IP-SAN, LAN cables are used to connect hosts to storage systems. The
cable port on the host is called a network interface card (NIC). In order to
use an NIC, the iSCSI software must be installed ahead of time on the host.
The cable port on the storage system is called a port (P) on a channel adapter
(CHA) used for iSCSI connections.
A logical unit (LU) contained in a storage system is the target of input to, or
output from, the host. You can divide an LU into multiple areas. Each area
after the division is called a Dev. The Dev is equivalent to a partition. A route
that connects a host and an LU is called a physical path, and a route that
connects a host and a Dev is called a path. When an LU has been divided into
multiple Devs, the number of paths set to the LU is equal to the number that
is found by multiplying the number of physical paths by the number of Devs
in the LU.
HDLM assigns an ID to a physical path and manages the paths on a physical-
path basis. When you use HDLM, there is no need to consider the difference
between a physical path and a path. Thus, hereafter both physical paths and
paths might be called paths, without a distinction being made between the
two. The ID that HDLM assigns for each physical path is called an
AutoPATH_ID. Also, a path might be called a management target.
The following figure shows the configuration of an HDLM system using an IP-
SAN.
Figure 2-2 Configuration of an HDLM System When Using an IP-SAN
The following table lists the HDLM system components when using an IP-SAN.
HDLM Functions
2-5
Hitachi Dynamic Link Manager (for Linux®) User Guide