HP Hitachi Dynamic Link Manager Software User Manual

Page 17

The ability to distribute a load across multiple paths. This is also known as

load balancing.

When a host is connected to a storage system via multiple paths, HDLM

can distribute the load across all the paths. This prevents one, loaded

down path from affecting the processing speed of the entire system.
For details on load balancing, see

The ability to continue running operations between a host and storage

system, even if there is a failure. This is also known as performing a failover.

When a host is connected to a storage system via multiple paths, HDLM

can automatically switch to another path if there is some sort of failure in

the path that is currently being used. This allows operations to continue

The ability to bring a path that has recovered from an error back online. This

is also known as performing a failback.

If a path is recovered from an error, HDLM can bring that path back

online. This enables the maximum possible number of paths to always be

available and online, which in turn enables HDLM to better distribute the

load across multiple paths.
Failbacks can be performed manually or automatically. In an automatic

failback, HDLM automatically brings a path back online on the host side

when the user has fixed the physical fault in the path.
For details on performing failbacks, see

The ability to automatically check the status of any given path at regular
intervals. This is also known as path health checking.

Detects path errors by checking the path status at regular intervals. This

allows you to check for any existing path errors and to resolve them

promptly and efficiently.
For details on setting up and performing path health checking, see

This is implemented by functionality provided by VMware vSphere ESXi.

Overview of HDLM

1-3

Hitachi Dynamic Link Manager User Guide for VMware

This manual is related to the following products: