JANUS ADDCOORDINATOR

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Add a two-phase commit coordinator to a 2PC port.

See JANUS DEFINE for a discussion of when you need to issue the JANUS DEFINE command.

Syntax

JANUS ADDCOORDINATOR portName coordinatorName host portnum

Where each of the first four parameters is positional and required:

portName The name of the Janus 2PC port(s) to which the coordinator is being added. Wildcard characters may be used in portName, indicating that the coordinator is to be added to all previously defined 2PC ports matching the pattern. There must be at least one previously defined 2PC port matching portName. Any ports which match portName but have not yet been defined will not have coordinatorName added when they are subsequently defined. Note though that it doesn't really make sense to have multiple 2PC ports anyway since only the first started 2PC port will be used.
coordinatorName A 1-30 character name for the coordinator to which this Janus port will connect for two-phase commit services. The remote server must be an Imgine Two-Pase Commit Coordinator.
host The IP address or hostname for the device on which the coordinator specified by coordinatorName is running.
portnum The port number to which to connect to the coordinator on host.

ADDCOORD is a valid abbreviation for ADDCOORDINATOR.

Janus two-phase commit example

The following example defined a 2PC port and associates a coordinator called COORD with it:

JANUS DEFINE TWOPC * 2PC 20 JANUS ADDCOORD TWOPC COORD IMAGINEHOST.MYDOMAIN.COM 4567

While additional coordinators can be defined as in

JANUS DEFINE TWOPC * 2PC 20 JANUS ADDCOORD TWOPC COORD IMAGINEHOST.MYDOMAIN.COM 4567 JANUS ADDCOORD TWOPC COORD2 IMAGINEHOST2.MYDOMAIN.COM 4567

the coordinators must be Imagine servers that share the same DatabaseStore. Janus will attempt to split the load approximately evenly among all coordinators added to a port.

See also