Contents of the interfaces File

An interfaces file contains network information about all servers on your network, including SAP ASE, Backup Server, and XP Server, plus any other server applications, such as Replication Server, and any Open Server applications.

The network information in the file includes the server name, network name, or address of the host machine, and the port, object, or socket number (depending on the network protocol) on which the server listens for queries.

Each entry in an interfaces file can contain two types of lines:
  • Master lines – used by server applications to listen for queries over the network. This information is called a listener service.
  • Query lines – used by client applications to connect to servers over the network. This information is called a query service.

The network information contained in the master and query lines for a server is identical because a server listens for connection requests on the same port that clients use to request connections.

A server needs both master and query lines in its interfaces file, since servers sometimes act as clients to other servers.

A client’s interfaces file does not need a master line. It functions correctly with only a query line.

If Your Site has Multiple Installations

If you have more than one SAP ASE installation, each server’s interfaces file should contain information about all servers on the network.

If all of your server products are running on the same platform, you can create one master interfaces file and copy that file to each machine.

Heterogeneous and Homogeneous Environments

If the platforms are different, each platform may require a different format and configuration for its interfaces file. For example, a PC client uses network information in its interfaces file (sql.ini) to connect to SAP ASE running under UNIX, and how SAP ASE uses its interfaces file to connect to another server during a remote procedure call.

Establishing Network Connections in a Heterogeneous Environment
Image shows the PC clients connect to Adaptive Server through the sql.ini file, and one of the server connecting to the other server through a remote procedure call

If both a client and a server are running under UNIX, the same interfaces file is valid for both. For example, clients and SAP ASE servers running in a homogeneous environment can use copies of the interfaces file to establish connections. Because the two SAP ASE servers are running under the same operating system, they can use the same interfaces file or exact copies of the same file.

Establishing Network Connections in a Homogeneous Environment
Image shows two homogeneous clients connecting to two Adaptive Servers, harpo and chico through the sql.ini file