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Compaq AA-Q88CE-TE User Manual

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Partition Management
3.6 Managing Partitions

3.6.4.2 Programming Information

To set the partition backend priority list, program the

set_qualifier

argument

of the

rtr_set_info( )

call as follows:

rtr_qualifier_value_t

set_qualifiers[ 2 ];

char

*szNodeList = "your,list,of,node,names,here"

set_qualifiers[ 0 ].qv_qualifier = rtr_partition_be_priority_list;
set_qualifiers[ 0 ].qv_value

= &szNodeList;

set_qualifiers[ 1 ].qv_qualifier = rtr_qualifiers_end;
set_qualifiers[ 1 ].qv_value

= NULL;

3.6.5 Controlling Failover

In a system configured for maximum fault tolerance employing both shadows and
standbys, there is a choice to be made in case of the failure of the primary site.
The qualifier to the

SET PARTITION

command of

/FAILOVER_POLICY=

allows the

system operator to select one of the following policies that RTR should pursue in
selecting the new primary site in the event of a failure:

/FAILOVER_POLICY=STANDBY

causes RTR to choose a standby of the failed

primary (if any) to become the new primary. If there is more than one
standby, the operator may addition use the priority list feature (described
above) to control which standby is preferred. Depending on the size of the
journal of the failed primary, there will be a hold up in the processing of
transactions whilst the journal is recovered. This is the default behaviour.

/FAILOVER_POLICY=SHADOW

instructs RTR to make the active secondary (if

any) the new primary. A standby of the failed primary (if any) will be elected
to become the new secondary. This option gives the shortest fail over time,
but will move the primary to a different cluster that you may have located at
a different site.

/FAILOVER_POLICY=COMPATIBLE_PRE_V32

is a mode that will operate with

configurations that contain RTR routers running versions of the software
prior to V3.2. This mode will be automatically adopted if such routers exists
in or join the configuration.

3.6.5.1 Command Line Example

An example use of the

/FAILOVER_POLICY

qualifier:

RTR> SET PARTITION/FAILOVER_POLICY=SHADOW Facility1:Partition1

For more information see the SET PARTITION command in Chapter 6.

3.6.5.2 Programming Information

To set the partition failover policy, program the

set_qualifier

argument of the

rtr_set_info( )

call as follows:

rtr_qualifier_value_t

set_qualifiers[ 2 ];

rtr_partition_failover_policy_t newPolicy;

set_qualifiers[ 0 ].qv_qualifier = rtr_partition_failover_policy;
set_qualifiers[ 0 ].qv_value = &newPolicy;
set_qualifiers[ 1 ].qv_qualifier = rtr_qualifiers_end;
set_qualifiers[ 1 ].qv_value = NULL;

Legal values for

newPolicy

are:

rtr_partition_fail_to_standby

3–8 Partition Management