HP Hitachi Dynamic Link Manager Software - Manual (Page 161)

3. Creating an HDLM Environment
139
If this happens, change any of the following settings: the checking interval for
automatic failbacks, the intermittent error-monitoring interval, or the number of times
that the error needs to occur.
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:
# /usr/DynamicLinkManager/bin/dlnkmgr set -afb on -intvl 10
To enable the automatic failback function, set it to
on
. The checking interval can be
specified by the
-intvl
parameter. The previously specified value will be applied
when a checking interval is not specified. For example, if you turn off the automatic
failback function after the checking interval was specified as
5
minutes, and then you
turn it back on (but without specifying a checking interval) the
5
minutes that were
specified from before will be used again.
(4) Setting Up Intermittent Error Monitoring
Intermittent error monitoring is specifiable only when the automatic failback function
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 210. 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 for the number of times an error needs to occur,
make sure that the condition shown in (3) Setting Up the Automatic Failback Function
is satisfied.
To determine whether a path is invalid for an automatic failback, you can use the
results of the
dlnkmgr
command's
view
operation.
The following is an example of setting up intermittent error monitoring by using a
command:
# /usr/DynamicLinkManager/bin/dlnkmgr set -iem on -intvl 20
-iemnum 2