Set Up Service Instances Across a Wide Area Network (WAN)
Two service instances may form a single distributed system across a WAN. The interaction of the two service instances may follow one of the patterns described in the section on Design Patterns.
Call the two service instances A and B.
The cluster within each service instance uses an identifier
This example assigns
distributed_system_id = 1 to cluster A
distributed_system_id = 2 to cluster B.
Cluster gateway senders provide the communication path and construct that
propagates region operations from one cluster to another.
On the receiving end are cluster gateway receivers.
Creating a service instance also creates gateway receivers.
The procedures in this section assume that service instances communicate using TLS encryption.
Note: To set up more than two service instances across a WAN, set up the interaction between the first two service instances A and B following the directions in either Set Up a Bidirectional System or Set Up a Unidirectional System, as appropriate. After that, set up the interaction between service instance A and another service instance (called C) following the directions in either Set Up an Additional Bidirectional Interaction or Set Up an Additional Unidirectional Interaction, as appropriate.