Requirements for Client Load Balancing

Client guidelines for deploying a third-party load balancer that is connected directly to SAP Mobile Server client ports.

The load balancer must:

Balance connections at the TCP/IP level.
Perform all load balancing on client connections to the SAP Mobile Server cluster, independent of any other network device.
Connect directly to the client ports of each SAP Mobile Server in the cluster.

Support client request routing (that is, back-end server affinity) for nonpersistent HTTP connections, for these way the load balancer dispatches requests, based on the HTTP header or cookie:

Load Balancer Dispatches...	HTTP Header (or Cookie)
All client requests to Relay Servers	`ias-rs-sessionid`
Replication based synchronization (RBS) client requests directly to SAP Mobile Platform	`ml-session-id`
Other client requests directly to SAP Mobile Platform	`X-SUP-SESSID` (cookie)

For REST API applications, see also Reference topic in Developer Guide: REST API Applications, especially the HTTP Headers and Cookies subtopic.

Map reverse proxy ports to SAP Mobile Server ports.
If both new version clients (Sybase Unwired Platform 2.2.0 and later, SAP Mobile Platform 2.3 and later) and old version clients (Sybase Unwired Platform 2.1.x and earlier) are supported, set up Relay Servers between SAP Mobile Server and load balancers and route client requests based on ias-rs-sessionid.
If both replication-based synchronization (RBS) clients and other types of clients are supported, set up Relay Servers between SAP Mobile Server and load balancers and route client requests based on ias-rs-sessionid.

Note: To allow header inspection, the load balancer must be a transport-layer security (TLS) endpoint on HTTPS connections from mobile clients.