Steps for customizing the TN3270E Telnet server configuration data set

You can customize the TN3270E Telnet server by defining server, connection, and other configuration characteristics.

Before you begin

You need to create the data set in which you will put the configuration information. You must also specify the profile data set name on the PROFILE DD statement in the procedure JCL that is used to start Telnet. The data set must be defined with format fixed block, and must have a record length of 56-256. The block size must be evenly divisible by the record length.

If you are using multiple TN3270E Telnet servers, ensure that each server uses unique LU names, or define shared LU name groups. If you do not use unique LU names or create shared LU name groups, then the second server that uses the same LU name will not be able to establish a session; either the OPEN ACB request will fail or the cross-domain session request will fail.

For information about updating Telnet configuration, see Using the VARY TCPIP,tnproc,OBEYFILE command to update Telnet configuration.

Procedure

Perform the following steps to customize the TN3270E Telnet server configuration data set. A sample configuration is in SEZAINST(EZBTNPRF).

Define Telnet server characteristics. The minimum required definition is the TELNETPARMS block with the PORT statement. The following functions are optional:
- To associate Telnet with one TCP/IP stack, see Associating Telnet with one TCP/IP stack.
- To set up Telnet in a sysplex to share LU names, see Shared LU name groups for Telnet servers.
- To qualify a port with the destination IP address or link name to differentiate between Telnet services, see Qualified ports.
- To use multiple Telnet ports, see Multiple ports.
- To reduce ECSA storage use when supporting a large number of connections, see Reducing demand for ECSA storage.
Define connection characteristics at the server or port level.
- To determine the connection type, see Connection mode choices.
- For security, see Connection security.
- For persistence, see Connection persistence.
Understand the concept of mapping Objects to Client Identifiers. To understand the concept of mapping Objects to Client Identifiers, see Mapping Objects to Client Identifiers.
After you identify all the clients in your network, determine which clients have unique characteristics (for example, a particular client should use a certain LU name) and need to remain exact Client Identifiers, and which clients can be combined into Client Identifier groups using wildcard values.
Use LU name mapping statements to assign LU names to connections based on the Client Identifier. This step is required. See LU name mapping statements.
Use application mapping statements to facilitate session setup based on the Client Identifier. See Application mapping statements.
Use the connection parameters mapping statement to change connection parameters based on specific Client Identifiers. To extend connection mode, security, and persistence choices to Client Identifiers, see Connection parameters mapping statement.
Consider advanced topic features for additional Telnet functions.

Results

You know you are done when you do not receive errors after you apply the profile.