IBM i Version 7.2 Networking Telnet IBM Note Before using this information and the product it supports, read the information in “Notices” on page 99. This edition applies to IBM i 7.2 (product number 5770-SS1) and to all subsequent releases and modifications until otherwise indicated in new editions. This version does not run on all reduced instruction set computer (RISC) models nor does it run on CISC models. This document may contain references to Licensed Internal Code. Licensed Internal Code is Machine Code and is licensed to you under the terms of the IBM License Agreement for Machine Code. © Copyright International Business Machines Corporation 1998, 2013. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Telnet................................................................................................................... 1 What's new for IBM i 7.2..............................................................................................................................1 PDF file for Telnet........................................................................................................................................ 1 Telnet scenarios...........................................................................................................................................2 Telnet scenario: Telnet server configuration.........................................................................................2 Telnet scenario: Cascaded Telnet sessions...........................................................................................4 System request processing scenarios..............................................................................................5 Using a group job...............................................................................................................................6 Telnet scenario: Securing Telnet with SSL............................................................................................ 9 Configuration details for securing Telnet with SSL........................................................................10 Planning for the Telnet server................................................................................................................... 14 Virtual device descriptions...................................................................................................................14 Telnet security......................................................................................................................................15 Preventing Telnet access................................................................................................................15 Controlling Telnet access............................................................................................................... 16 Configuring the Telnet server.................................................................................................................... 19 Starting the Telnet server.....................................................................................................................19 Setting the number of virtual devices..................................................................................................20 Automatically configuring virtual devices...................................................................................... 20 Creating your own virtual devices.................................................................................................. 21 Restricting privileged users to specific devices and limiting sign-on attempts................................. 22 Setting the session keep-alive parameter...........................................................................................22 Setting inactive job timeout used by Telnet........................................................................................ 23 Assigning devices to subsystems........................................................................................................ 23 Activating the QSYSWRK subsystem...................................................................................................24 Creating user profiles........................................................................................................................... 24 IBM i supported emulation types........................................................................................................ 24 Configuring Telnet server for 5250 full-screen mode................................................................... 25 Configuring Telnet server for 3270 full-screen mode................................................................... 25 Supported 3270 terminal types................................................................................................27 Configuring Telnet server for VTxxx full-screen mode.................................................................. 27 Securing Telnet with SSL......................................................................................................................30 Configuring SSL on the Telnet server............................................................................................. 30 Removing port restrictions........................................................................................................31 Assigning a certificate to the Telnet server.............................................................................. 31 Enabling client authentication for the Telnet server................................................................32 Enabling SSL on the Telnet server............................................................................................ 34 SSL initialization and handshake....................................................................................................35 Managing the Telnet server....................................................................................................................... 36 Configuring Telnet printer sessions.....................................................................................................36 Requirements for Telnet printer sessions......................................................................................37 Telnet server print support to IBM i Access for Windows Telnet client.................................. 37 Ending the Telnet server session.........................................................................................................37 Ending device manager jobs................................................................................................................ 38 Using Telnet exit point programs.........................................................................................................38 Device initialization exit program................................................................................................... 40 Telnet exit point format INIT0100: Required parameter group..............................................40 INIT0100: Format of user description information................................................................. 42 INIT0100: Format of device description information..............................................................42 INIT0100: Format of connection description information...................................................... 44 Device termination exit program....................................................................................................47 iii Examples: Telnet exit programs.....................................................................................................47 Managing the Telnet client........................................................................................................................ 48 Controlling Telnet server functions from the client............................................................................ 49 5250 Telnet client sessions.................................................................................................................50 Starting a Telnet client session...................................................................................................... 50 3270 Telnet client sessions.................................................................................................................51 Starting a 3270 Telnet client session.............................................................................................52 3270 full-screen considerations.................................................................................................... 53 Using a display station....................................................................................................................54 3270 keyboard mapping for Telnet servers...................................................................................55 VTxxx Telnet client sessions................................................................................................................ 58 Starting a VTxxx Telnet client session............................................................................................58 VTxxx full screen considerations....................................................................................................59 VTxxx emulation options................................................................................................................ 63 VTxxx key values.............................................................................................................................64