What Is Hdlm - Hitachi XP P9500 User Manual

1. Overview of HDLM

1.1 What is HDLM?

With the widespread use of data warehousing and increasing use of multimedia data,
the need for high-speed processing of large volumes of data on networks has rapidly
grown. To satisfy this need, networks dedicated to the transfer of data, such as SANs,
are now being used to provide access to storage systems.
HDLM manages the access paths to these storage systems. HDLM provides the ability
to distribute loads across multiple paths and switch to another path if there is a failure
in the path that is currently being used, thus improving system availability and
reliability.
Figure 1-1: Between Hosts and Storage Systems illustrates the connections between
various hosts and storage systems. A server on which HDLM is installed is called a
host.
Figure 1-1: Between Hosts and Storage Systems
HDLM supports the following storage systems:
• Hitachi AMS2000/AMS/WMS/SMS series
• Hitachi USP
• Lightning 9900 series
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