Maintaining HCON

To maintain HCON you can:

• Add and delete users from the registered user list.
• Create new session profiles for existing users. For example, if a new 3270 Connection Adapter is added to the system, you must create DFT profiles for using the new device.
• Recover from interrupted file transfers.
• Stop interrupted sessions or free up system resources if a session is interrupted.
• Troubleshoot problems; for example:
  • Check session profiles to ensure all the characteristics are correctly defined.
  • Check the host configuration as well as the host hardware device connections.
  • Use the ps command to ensure:
    • The hcondmn subsystem is running at all times.
    • Display sessions running explicitly have an e789 process is in the process display.
    • Each individual session has one e789x process.
    • A SNA-attached DFT display session has one e789lus process.
    • File transfers in progress have the dfxfer process running.
    • HLLAPI program or file transfers running implicitly have an associated e789x process in the process display.
    • A host addressable printer session has an e789pr process and the correct e789x child process.

Recovering from Interrupted HCON File Transfers

Users can interrupt file transfers before completion. Any unrecoverable communication error can interrupt a file transfer. An interrupted file transfer can be started again without loss of data. When a transfer is interrupted, the state of the transfer is saved in a restart file in the user's $HOME directory. A maximum of five transfer requests can be saved in restart files.

Restart an interrupted file transfer using the fxfer command with the -R flag. The -R flag brings up a menu displaying these choices:

• Restart the file transfer.
• Delete the restart file.
• Exit from the file transfer program.

The fxfer command restarts the previous file transfer using the information saved in the $HOME/x_fxfer.r or $HOME/i_fxfer.r file. The $HOME/i_fxfer.r file contains restart information for implicit file transfers. The $HOME/x_fxfer.r file contains restart information for explicit file transfers.

If the user runs a new file transfer, after a file transfer has been interrupted, the fxfer command reminds the user a restart file exists. A restart menu displays with these choices:

• Restart the interrupted file transfer.
• Delete the restart file.
• Exit from the file transfer program.
• Continue with the current file transfer.

If the user elects to continue the current file transfer, the restart file for the previous transfer can be deferred or deleted.

If the host communication is lost or disconnected, an implicit file transfer attempts to recover by reconnecting and logging back on to the host using the dfxfer process. The length of time the dfxfer process attempts recovery is determined by the File Transfer Recovery Time value in the session profile. Once the host communication is established, the dfxfer process begins the file transfer. If communication cannot be established, the file transfer program generates a restart file.

Stopping Interrupted HCON Sessions with the e789cln Command

HCON sessions can be interrupted by a power failure or a loss of connection to the host. If a session is interrupted, the processes associated with the session may not be stopped. Stop these processes with the e789cln command. The e789cln command stops specified HCON sessions and the processes associated with those sessions. These guidelines govern the use of the e789cln command.

• Any HCON user can use the command to stop that user's sessions.
• A root user can use the command to stop the sessions of other users.
• Use the command to stop one session, multiple sessions, or all sessions for a given user.
• Use the command only when there is a problem requiring the processes associated with a session to be stopped.
• Using the command to stop a session in progress normally causes errors.

  Note: Use the QUIT emulator key (by default, the Ctrl-D key sequence) to stop a normal session.