HP Hitachi Dynamic Link Manager Software - Manual (Page 214)

3. Creating an HDLM Environment
192
If you set the number of times that the error needs to occur to
1
, the above condition
does not need to be satisfied.
The following is an example of setting up automatic failback by using a command:
# /opt/DynamicLinkManager/bin/dlnkmgr set -afb on -intvl 10
To enable the automatic failback function, set it to
on
. When
on
is specified, you can
use the
-intvl
parameter to specify the checking interval. If the checking interval is
not specified, the value that was previously specified will be applied. For example,
specify the auto failback as
off
after specifying the checking interval to five minutes
and executing. Then, when executing after specifying the auto failback as
on
without
specifying the checking interval, the five minutes that were specified previously will
be applied again.
(4) Setting Up Intermittent Error Monitoring
You can set the intermittent error monitoring only when automatic failback 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.
When a value of
2
or more is specified in the number of error occurrence, make sure
that the condition shown in (3) Setting Up the Automatic Failback Function is
satisfied. To determine whether an intermittent error is occurring in a path, you can use
the execution results of the
dlnkmgr
command's
view
operation.
The following shows an example of executing the command to set intermittent error
monitoring.
# /opt/DynamicLinkManager/bin/dlnkmgr set -iem on -intvl 20
-iemnum 2
To enable intermittent error monitoring, set it to
on
. Otherwise, set it to
off
. When
on
is specified, you can use the
-intvl
and
-iemnum
parameters to specify intermittent
error conditions (the conditions used by the system to determine whether an
intermittent error is occurring). Specify the monitoring interval for an intermittent