Steps for verifying server operation

Determine whether the server is active and is using the correct port.

About this task

Figure 1 shows the decisions involved for verifying server operation.

Figure 1. Overview of verifying server operation

Perform the following steps to verify server operation:

1. Ensure that the server is started. If not, start the server.
2. Use the Netstat SOCKETS/-s command to determine which port the server is listening on, filtered on the application's job name (-E option for z/OS® UNIX, CLIENT keyword for TSO and Operator commands). For example

   NETSTAT SOCKETS (CLIENT SMTP

   If the server is not listening on the correct port, configure it correctly. For basic information about the Netstat SOCKETS/-s command, see z/OS Communications Server: IP System Administrator's Commands for details. For details on server configuration, see z/OS Communications Server: IP Configuration Reference.

3. Ensure that there is a PORT statement in the TCP/IP profile data set, to reserve the port for the server. If the server is started but not using the correct port, then a PORT statement might be missing. See z/OS Communications Server: IP Configuration Reference for more information about the PORT statement.
4. Use the Netstat SOCKETS/-s command to determine whether a different server is using the port filtered on the port number (-p option for z/OS UNIX, PORT keyword for TSO and Operator commands). Unless the SHAREPORT keyword is specified on the PORT statement, only one server can be listening on a TCP port. See z/OS Communications Server: IP Configuration Reference for more information about the PORT statement.
5. Check the PORT statement for the server to determine whether the SAF keyword has been specified. If so, then port access control is in effect for the port. See z/OS Communications Server: IP Configuration Guide for more information about port access control. Ensure that the user ID associated with the server is permitted to the security resource name represented by the SAF keyword value. See the description of the PORT statement SAF keyword in the z/OS Communications Server: IP Configuration Reference for information about the security resource name. If the SAF keyword was not specified on the PORT statement, and the server belongs to the z/OS Communications Server product, see z/OS Communications Server: IP Configuration Reference for configuration information that is specific to the server.