Hitachi XP P9500 User Manual page 208

The explanation for the following sub-parameter describes how to specify
the checking interval.
-intvl checking-interval
-afb {on [-intvl checking-interval]|off}
Enables or disables automatic failbacks.
on: Enabled
off: Disabled
Enabling automatic failbacks might automatically place paths online that
were intentionally placed offline (for example, paths placed offline for
maintenance work).
If you want to prevent such paths from automatically being placed online,
disable this function. When intermittent errors occur in paths or storage
systems, statuses of paths alternates between the online and offline
status frequently, thus decreasing I/O performance.
Automatic failbacks are performed on the following types of paths:
¢
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To prevent intermittent errors from deteriorating I/O performance, we
recommend that you also enable intermittent error monitoring when the
automatic failback function is enabled. Intermittent error monitoring is
specifiable only when automatic failbacks are enabled.
See
Failback Function and Intermittent Error Monitoring and the Executable
Operations on page 6-24
failbacks and intermittent error monitoring.
When you specify on, specify the checking interval by specifying the
parameter immediately following on. If you do not specify a checking
interval, path statuses will be checked in the following way:
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6-20
Specify the checking interval between path health checks. Specify a
value from 1 to 1440 minutes depending on the user environment.
When you change the checking interval, the new setting takes effect
immediately. When the checking interval is shortened and the
checking interval after the change (from the end of the previous path
health check) has already elapsed, the path health check will start
over.
The path health check interval setting remains stored in the system
even if you disable the function by changing the path health checking
to off. Therefore, when you re-enable path health checking and do
not change the interval, the path health interval stored in the system
is used.
Paths where an error occurred and for which the KAPL08022-E
message was displayed.
Path where an error occurred during the startup of the HDLM
manager.
Table 6-5 Relationship Between the Setting for the Automatic
When the checking interval has not been specified before:
Every minute (default setting)
When the checking interval has been specified before:
Command Reference
Hitachi Dynamic Link Manager User Guide (for Windows(R))
for the relationship between automatic