Telnet commands

Telnet commands are TCP/IP commands. You must specify the procedure name on all commands; otherwise, the command is processed by the default TCP/IP stack instead of by the Telnet procedure. For example, assuming that the Telnet procedure name is TN3270E, the profile display command is as follows:

D TCPIP,TN3270E,PROFILE

If the procedure does not exist or if you incorrectly type the TCPIP keyword, then the command is assumed to be a TCP/IP command and a TCP/IP error message is displayed.

You use the following VARY and DISPLAY commands to change and monitor Telnet functions and to debug problems. Telnet VARY and DISPLAY commands are described in z/OS Communications Server: IP System Administrator's Commands.

  • Use Telnet VARY commands to change the state of Telnet ports, enable or disable the use of certain Telnet LU names, and manage diagnostic tools.
    • VARY TCPIP,tnproc,QUIESCE,PORT blocks any new connection requests but allows existing connections to continue activity.
    • VARY TCPIP,tnproc,RESUME,PORT ends the quiesce state and allows new connection requests.
    • VARY TCPIP,tnproc,STOP,PORT ends connections on the port and closes the port.
    • VARY TCPIP,tnproc,OBEYFILE starts, restarts, or changes a port by updating the Telnet profile. Use the VARY TCPIP,tnproc,STOP and VARY TCPIP,tnproc,OBEYFILE commands to stop a Telnet port and then restart that port or start a new port without stopping the TCP/IP stack. You can also use these commands to increase the level of participation in the Telnet XCF group. A Telnet server that has joined the group becomes a standby LUNS, even if you used an OBEYFILE command to specify it to be a primary LUNS.
      Tip: When you issue a VARY TCPIP,tnproc,OBEYFILE command, the TELNETPARMS and BEGINVTAM blocks are required for each port that you start or modify.
    • VARY TCPIP,tnproc,ACT,luname activates LUs for use by the Telnet server. Specify ALL for luname to activate all inactive LUs with one command. This command has no effect on the VTAM® state of the LU.
    • VARY TCPIP,tnproc,INACT,luname deactivates LUs for use by the Telnet server. If an LU is already in use, the command fails. This command has no effect on the VTAM state of the LU.
    • VARY TCPIP,tnproc,DEBUG,OFF turns off all debug activity that might have been turned on to debug a problem.
    • VARY TCPIP,tnproc,ABENDTRAP sets an abend trap based on unique Telnet return codes set in Telnet modules.
  • Use Telnet VARY commands to change the state of a LUNS, and to enable or disable the use of certain LU names by a LUNS.
    • VARY TCPIP,tnproc,LUNS,START starts the takeover process by which a standby LUNS becomes the active LUNS.
    • VARY TCPIP,tnproc,LUNS,QUIESCE instructs a standby LUNS to stop monitoring the active LUNS. In case of a LUNS failure, this Telnet server will not be a takeover candidate. The Telnet server must be a takeover candidate for you to make changes to the LUNS using the OBEYFILE command.
    • VARY TCPIP,tnproc,LUNS,RESUME ends the quiesce state and instructs a LUNS to resume monitoring the active LUNS. In case of a LUNS failure, this Telnet will be a takeover candidate.
    • VARY TCPIP,tnproc,LUNS,ACT,luname activates LUs for use by the LUNS. Specify ALL for luname to activate all inactive LUs with one command. This command has no effect on the VTAM state of the LU.
    • VARY TCPIP,tnproc,LUNS,INACT,luname deactivates LUs for use by the LUNS. If an LU is already in use, the command fails. This command has no effect on the VTAM state of the LU.
  • Use Telnet DISPLAY commands to review classic Telnet information.
    • D TCPIP,tnproc,PROFile displays summary or detail information about parameter statements from the TELNETGLOBALS or TELNETPARMS blocks.
    • D TCPIP,tnproc,OBJect displays summary or detail information about mapping statements from the Object perspective.
    • D TCPIP,tnproc,CLientID displays summary or detail information about mapping statements from the Client Identifier perspective.
    • D TCPIP,tnproc,CONN displays summary or detail information about client connections.
    • D TCPIP,tnproc,INACTLUS displays all LUs that were deactivated by the operator or by Telnet as a result of OPEN ACB or multilevel security problems.
    • D TCPIP,tnproc,STOR displays the maintenance level of a module or the amount of storage used by Telnet.
  • Use Telnet DISPLAY commands to review information about Telnet in an XCF group.
    • D TCPIP,tnproc,XCF<,GRoup> displays the status of all members of the Telnet XCF group.
    • D TCPIP,tnproc,XCF,STats displays the performance status of the XCF Telnet server. If the Telnet server is a LUNS, the performance statistics between it and all LUNRs are reported.
  • Use Telnet DISPLAY commands to review information about Telnet performing as a LUNS.
    • D TCPIP,tnproc,LUNS,OBJect displays summary or detail information about shared LUNR Objects on the LUNS.
    • D TCPIP,tnproc,LUNS,INACTLUS displays all the LUs that are inactive on the LUNS.