Multiple connection types

A single instance of the database server can provide more than one type of connection.

The following figure illustrates a configuration with more than one type of connection. The database server is on host river. Client A connects to the database server with a shared-memory connection because shared memory is fast. Client B must use a network connection because the client and server are on different computers.

When you want the database server to accept more than one type of connection, you must take the following actions:
  • Add DBSERVERNAME and DBSERVERALIASES entries in the onconfig file.
  • Add an sqlhosts entry for each database server/connection type pair.
For the configuration in the following figure, the database server has two dbserver names: river_net and river_shm. The onconfig file includes the following entries:
DBSERVERNAME               river_net
DBSERVERALIASES            river_shm
Figure 1: An example of a UNIX™ client/server configuration that uses multiple connection types

This figure is described in the surrounding text.

The dbserver name used by a client application determines the type of connection that is used. Client A uses the following statement to connect to the database server:
CONNECT TO '@river_shm'

In the sqlhosts file, the nettype associated with the name river_shm specifies a shared-memory connection, so this connection is a shared-memory connection.

Client B uses the following statement to connect to the database server:
CONNECT TO '@river_net'

In the sqlhosts file, the nettype value associated with river_net specifies a network (TCP/IP) connection, so Client B uses a network connection.