Hitachi XP P9500 User Manual page 371

not change the interval, the path health interval stored in the system
is used.
-afb {on [-intvl checking-interval]|off}
Enables or disables automatic failback.
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).
When intermittent errors occur in paths or storage systems, path status
alternates between the online and offline status frequently, so I/O
performance might deteriorate.
Automatic failbacks are performed on the following types of paths:
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.
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 Table 6-5 Relationship Between the Setting for the Automatic
Failback Function and Intermittent Error Monitoring and the Executable
Operations on page 6-22
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:
When the checking interval has not been specified before:
¢
Every minute (default setting)
When the checking interval has been specified before:
¢
The previously used interval
The explanation for the following sub-parameter describes how to specify
the interval between path status checks.
-intvl checking-interval
Specify the interval between path status checks. Specify a value from
1 to 1440 minutes. The default is 1. Specify an interval appropriate
for your operating environment.
If intermittent error monitoring is on and the number of times that the
error is to occur is set to a value of 2 or more, the following condition
must be satisfied:
error-monitoring-interval >= checking-interval-for-automatic-
failback x number-of-times-error-is-to-occur-during-
Hitachi Dynamic Link Manager User Guide (for Linux(R))
for the relationship between automatic
Command Reference
6-19