HP Hitachi Dynamic Link Manager Software User Manual
Page 160
3. Creating an HDLM Environment
138
Set it to
on
to enable load balancing. Otherwise, set it to
off
. When you set
on
,
specify one of the following algorithm values after the
-lbtype
option:
•
rr
for the Round Robin algorithm
•
exrr
for the Extended Round Robin algorithm
•
lio
for the Least I/Os algorithm
•
exlio
for the Extended Least I/Os algorithm
•
lbk
for the Least Blocks. algorithm
•
exlbk
for the Extended Least Blocks algorithm
The type of algorithm specified by the
-lbtype
parameter remains stored in the
system, even if, you disable the load balancing function by specifying
-lb
off
. If you
decide to re-enable load balancing at a later time, and you do not specify an algorithm,
load balancing will still be executed by using the algorithm that was previously
specified.
(2) Setting Up Path Health Checking
You can choose whether you want to use path health checking.
The following is an example of how to set up path health checking by using a
command:
# /usr/DynamicLinkManager/bin/dlnkmgr set -pchk on -intvl 10
When path health checking is enabled by specifying
on
for the
-pchk
parameter, you
can also specify the
-intvl
parameter, in order to specify the checking interval. If the
checking interval is not specified, then the previously specified value will be
automatically applied. For example, if you turn off path health checking after the
checking interval was specified as
15
minutes, and then you enable path health
checking again (but without specifying a checking interval) the
15
value that was
specified from before will be used again.
(3) Setting Up the Automatic Failback Function
When intermittent error monitoring is enabled and the number of error occurrences is
2
or more, the following condition must be satisfied.
error-monitoring-interval >= checking-interval-for-automatic-failbacks
x
number-of-times-an-error-is-to-occur-during-intermittent-error-monitoring
If this condition is not satisfied, an error will occur and the warning message
KAPL01080-W will be output.