HP Hitachi Dynamic Link Manager Software - Manual (Page 138)

Setting Up the Automatic Failback Function
When intermittent error monitoring is enabled and the number of error
occurrences is 2 or more, the following condition must be satisfied.
error-monitoring-interval >= checking-interval-for-automatic-
failbacks x number-of-times-an-error-is-to-occur-during-intermittent-
error-monitoring
If this condition is not satisfied, an error will occur and the warning message
KAPL01080-W will be output.
If this happens, change any of the following settings: the checking interval
for automatic failbacks, the intermittent error-monitoring interval, or the
number of times that the error needs to occur.
If you set the number of times that the error needs to occur to 1, the above
condition does not need to be satisfied.
• Setting up automatic failback by using the set operation
The following is an example of setting up automatic failback by using a
command:
>dlnkmgr set -afb on -intvl 10
To enable the automatic failback function, set it to on. The checking
interval can be specified by the -intvl parameter. The previously
specified value will be applied when a checking interval is not specified.
For example, if you turn off the automatic failback function after the
checking interval was specified as 5 minutes, and then you turn it back on
(but without specifying a checking interval) the 5 minutes that were
specified from before will be used again.
Setting Up Intermittent Error Monitoring
Intermittent error monitoring is specifiable only when the automatic failback
function is enabled. To prevent an intermittent error from reducing I/O
performance, we recommend that you monitor intermittent errors when
automatic failback is enabled.
When intermittent error monitoring is enabled, you can specify intermittent
error conditions. The default value for the intermittent error-monitoring
interval is 30. The default value for the number of error occurrences is 3.
The system assumes that an intermittent error has occurred if the specified
number of times that the error needs to occur is reached during the specified
monitoring interval. A path that is assumed to have an intermittent error is
excluded from performing an automatic failback. Intermittent error
monitoring starts right when the path is recovered from the error by
performing an automatic failback. Monitoring is performed on each, individual
path.
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Creating an HDLM Environment
Hitachi Dynamic Link Manager User Guide (for Windows(R))