HA_FOC_ORDER configuration parameter

Use the HA_FOC_ORDER configuration parameter to define a single connection-management failover rule for a high-availability cluster of servers.

onconfig.std value
HA_FOC_ORDER SDS,HDR,RSS
values
A list of secondary server types, which are separated by commas and listed in priority order. For example, the default value of SDS,HDR,RSS means that the primary server fails over to the SD secondary server, then the HDR secondary server, and then the RS secondary server.
  • HDR = High-availability data replication server
  • RSS = Remote stand-alone secondary server
  • SDS = Shared-disk secondary server

MANUAL = Disable automated failover for all Connection Managers in the cluster.

separators
Separate values with a comma.
takes effect
After you edit your onconfig file and restart the database server.
When you reset the value dynamically in your onconfig file by running the onmode -wf command.
When you reset the value in memory by running the onmode -wm command.
After you run the SQL administration API task() or admin() function with the -wf HA_FOC_ORDER=value or -wm HA_FOC_ORDER=value arguments.

Usage

If the HA_FOC_ORDER configuration parameter is set on the primary database server of a high-availability cluster, every Connection Manager that connects to the primary server adopts the setting. The value replaces the connection unit's ORDER=rule failover-sequence rule. Each database server in the high-availability cluster then adopts the primary server's HA_FOC_ORDER configuration parameter value for its own HA_FOC_ORDER configuration parameter.

If the HA_FOC_ORDER configuration parameter on the primary server is set to MANUAL, automated failover is disabled on all Connection Managers that manager the primary server's cluster.

If the FOC ORDER value for a connection unit in a Connection Manager's configuration file is set to DISABLED the Connection Manager does not perform failover for that connection unit.

Read syntax diagramSkip visual syntax diagram
Syntax for the HA_FOC_ORDER configuration parameter

                   .-,-------.     
                   V         |     
                 .---+-SDS-+-+-.   
                 |   +-HDR-+   |   
                 |   '-RSS-'   |   
>>-HA_FOC_ORDER--+-MANUAL------+-------------------------------><

Example

In the following example, you have two Connection Managers that are configured to manage a cluster of three servers.

The three servers are:
  • server_1 (primary server)
  • server_2 (SD secondary server)
  • server_3 (HDR secondary server)
The first Connection Manager has the following configuration file:
NAME connection_manger_1

CLUSTER cluster_1
{
   INFORMIXSERVER servers_1
   SLA sla_1 DBSERVERS=ANY
   FOC ORDER=ENABLED \
       PRIORITY=1
}
The second Connection Manager has the following configuration file:
NAME connection_manger_2

CLUSTER cluster_1
{
   INFORMIXSERVER servers_1
   SLA sla_2 DBSERVERS=ANY
   FOC ORDER=ENABLED \
       PRIORITY=2
}
The onconfig file of server_1 has the following value:
HA_FOC_ORDER SDS,HDR
When connection_manger_1 and connection_manger_2 connect with server_1, their configurations become:
NAME connection_manger_1

CLUSTER cluster_1
{
   INFORMIXSERVER servers_1
   SLA sla_1 DBSERVERS=ANY
   FOC ORDER=SDS,HDR \
       PRIORITY=1
}
NAME connection_manger_2

CLUSTER cluster_1
{
   INFORMIXSERVER servers_1
   SLA sla_2 DBSERVERS=ANY
   FOC ORDER=SDS,HDR \
       PRIORITY=2
}

The values of the HA_FOC_ORDER entries in the onconfig files of server_2 and server_3 are updated to SDS,HDR.


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