HP Hitachi Dynamic Link Manager Software - Manual (Page 33)

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, Hitachi AMS2000 series
#1 , Hitachi SMS series #1 , HUS100 series #1 , 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
2-15
Hitachi Dynamic Link Manager User Guide for VMware ®