HiCommand Dynamic Link Manager (HDLM) for Windows Systems User's Guide (HIT5201-96001, January 2008)

HiCommand
®
Dynamic Link Manager (HDLM) for Windows
®
Systems User’s Guide 229
To specify the interval between path status checks (in minutes), use -intvl checking-
interval. Specify a value from 1 to 1440 minutes as appropriate for your operation
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-intermittent-error-monitoring
If this condition is not satisfied, the KAPL01080-W message is output and an error occurs. In
such a case, change any of the following settings: the checking interval for automatic
failback, the intermittent error monitoring interval, or the number of times that the error is
to occur.
When you set the number of times that the error is to occur to 1, the above condition does
not need to be satisfied.
When you change the error monitor interval while monitoring for an intermittent error is
operating, 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
status check) has already elapsed, the path status check will start immediately.
This setting remains stored in the system, even if you disable the function by changing the
setting of automatic failback to off. Therefore, when you re-enable automatic failback and
do not change the interval, path status checks are executed at the interval stored in the
system.
When you upgrade from HDLM 3.0 or 3.1 to 5.0 or later, and the -pchk parameter was set
to on in the previous version, the -afb parameter will be set to on in the new version. The
value of the -intvl parameter will be set to the same value as the checking interval of the
-pchk parameter.
To enable or disable intermittent error monitoring, use -iem { on [-intvl error-
monitoring-interval] [-iemnum number-of-times-error-is-to-occur] |
off }.
 on: Enabled
 off: Disabled
Intermittent error monitoring can be set only when automatic failback is set to on. When
you use automatic failback, we recommend that you set intermittent error monitoring to on
to prevent an intermittent error from reducing I/O performance.
If on is specified, in the subsequent parameters specify the intermittent error monitoring
interval and the number of times that the error is to occur. The system assumes that an
intermittent error is occurring if the specified number of times that the error is to occur is
reached during the monitoring interval (from the time that the monitoring interval starts,
until the specified interval ends). A path that is assumed to have an intermittent error is
excluded from automatic failback. Intermittent error monitoring is performed on individual
paths. Intermittent error monitoring starts when a path is recovered from the error by using
automatic failback.