HP XP P9500 Storage - Manual (Page 47)

number of times that the error needs to occur. If an error occurs on a
particular path the specified number of times within the specified error-
monitoring interval, then an intermittent error will occur on the path. For
example, if you specify 30 for the error monitoring interval and 3 for the
number of times that the error needs to occur, the path is determined to
have an intermittent error if an error occurs 3 or more times in 30 minutes.
You can set up intermittent error monitoring by executing the dlnkmgr
command's set operation.
Intermittent error monitoring can be used only when automatic failback has
already been enabled. The values that can be specified for intermittent error
monitoring depend on the values specified for automatic failbacks. For details
on how to specify the settings, see set (Sets Up the Operating Environment)
on page 6-14 .
Intermittent Error Monitoring Actions
Intermittent error monitoring is performed on each path, and it automatically
starts as soon as a path is recovered from an error by using the automatic
failback function.
This subsection describes the following intermittent error monitoring actions:
• When an intermittent error occurs
• When an intermittent error does not occur
• When the conditions for an intermittent error to occur are changed during
error monitoring
When an Intermittent Error Occurs
When an error occurs on a path a specified number of times within a specified
interval, the error monitoring will finish and the path is determined to have
an intermittent error, upon which the path is removed from those subject to
automatic failbacks. The path that is removed will remain in the error status
until the online operation is performed. However, if the path satisfies certain
conditions (see Figure 2-11 Path Status Transitions on page 2-23 ), it will be
subject to automatic failbacks and change to the Online status.
Figure 2-12 Action What Will Happen When an Intermittent Error Occurs on a
Path on page 2-26 shows what will happen when an intermittent error
occurs. For this example, the path is determined to have an intermittent error
when the error occurs 3 or more times within 30 minutes. The events that
occur are described by using the time arrows.
HDLM Functions
2-25
Hitachi Dynamic Link Manager User Guide (for Linux(R))