Detecting Errors By Using Path Health Checking - Hitachi XP P9500 User Manual

Restarting the HDLM manager
Restarting the host
#1
When you turn the intermittent error monitoring function off, information
about paths not subject to automatic failback will be reset. If you do not
want to reset the information about paths not subject to automatic
failback when you turn the intermittent error monitoring function off,
change the target paths to Offline(C).
#2
The number of errors and the time passed since error monitoring had
started are both reset to 0, and then monitoring restarts from the time
the setting change is made in accordance with the changed monitoring
conditions.
#3
The number of errors and the time passed since error monitoring had
started are both reset to 0, and then monitoring restarts from the time
the HDLM manager starts.

Detecting Errors by Using Path Health Checking

HDLM can check the status of paths for which I/O operations are not being
performed at regular intervals. This function is called path health checking.
Without path health checking, an error cannot be detected unless an I/O
operation is performed, because the system only checks the status of a path
when an I/O operation is performed. With path health checking, however, the
system can check the status of all online paths at regular intervals regardless
of whether I/Os operations are being performed. If an error is detected in a
path, the path health checking function switches the status of that path to
Offline(E) or Online(E). You can use the dlnkmgr command's view
operation to check the path error.
User operation
Placing the path Online
while intermittent error
monitoring is being
performed
HDLM Functions
Hitachi Dynamic Link Manager User Guide (for Linux(R))
Number of
Information
errors and time
about paths
passed since
not subject to
error
automatic
monitoring
started
Inherited (Not applicable)
If a path has
been removed
from the paths
subject to
automatic
monitoring, that
path is no
longer
monitored.
Inherited
#3
Reset
Reset Reset
failback
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