Relay Server Clusters

A Relay Server cluster enables load balancing and redundant Relay Servers, to improve system availability.

Load balancing across multiple Relay Servers requires a front-end load balancing mechanism, such as a layer 4 network switch.

A Relay Server cluster (or farm) consists of one or more Relay Server instances that service the same set of RSOEs (each associated with an Unwired Server instance).

Participation in a cluster is enabled by a flag in each Relay Server's configuration file.

In a Relay Server cluster, the only cluster-specific behavior occurs when the RSOE initiates connection to a Relay Server and queries it for connection information.

When in a cluster, each Relay Server returns connection information for itself, and all other Relay Servers in the cluster.
When not in a cluster, the Relay Server returns connection information for itself only.

When the RSOE receives connection information for more than one Relay Server, it opens connections to all Relay Servers in the cluster.

Unwired Server connection to Relay Servers in cluster