Hitachi Dynamic Link Manager Software Users Guide for VMWare

Figure 2-10 Path Switching

Automatic Failbacks

When a path recovers from an error, HDLM can automatically place the

recovered path back online. This function is called the automatic failback

function.

When using the Hitachi AMS/WMS series, HDLM will select the next path to be

used first from among the online owner paths, and then from the online non-

owner paths. As a result, if an owner path recovers from an error, and then

HDLM automatically places the recovered path online while a non-owner path

is in use, the path will be automatically switched over from the non-owner

path to the owner path that just recovered from the error.

When the Universal Storage Platform V/VM series, Virtual Storage Platform

series, VSP G1000 series, Hitachi AMS2000 series

, Hitachi SMS series

HUS100 series

, or HUS VM is being used, all the paths are owner paths. As

a result, if the path that was previously used recovers from an error, and

then HDLM automatically places the recovered path online, the path that is

currently being used will continue to be used (as opposed to switching over to

the path that was just recovered).

HDLM Functions

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Hitachi Dynamic Link Manager (for VMware®) User Guide