X11 Port Forwarding
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To use X11 port forwarding, include the ForwardX11 in the client configuration file (SSH_CONFIG.), or use one of the following options to the SSH command:
The +x option, which enables untrusted X11 connections (default)
The +X option, which enables trusted X11 connections
The -x option, which disables X11 connections
When X11 port forwarding is enabled on both the SSH client and server, you can use SSH to connect to an SSH server and invoke X11 client programs there, while having them appear on your local display. You can also "chain" port forwarding across multiple systems, even if the intermediate systems are not running the X11 server. For example, from SYSTEM1 you can use SSH to connect to SYSTEM2, and then from SYSTEM2 connect to SYSTEM3. An X11 client application running on SYSTEM3 will be displayed securely on SYSTEM1.
X11 access to an OpenVMS X11 server requires enabling access to the X11 client. On HP DECwindows Motif for OpenVMS Systems, this can be done through the Style Manager/security option:
Add the appropriate values for node and user name, and the value tcpip as the transport. Details of how to enable access on other platforms may differ.
To direct output to the forwarded X11 server port, enter the following command:
$ SET DISPLAY/CREATE/TRANSPORT=TCPIP/NODE=Xserver
For Xserver, specify the name of the SSH server. To direct output to the local SSH server, enter the keyword LOCAL. To verify that the settings are correct, enter the following commands:
$ SHOW DISPLAY Device: WSA777: [user] Node: sshclient.myplace.com Transport: TCPIP Server: 10 Screen: 0$ SHOW LOGICAL DECW$DISPLAYFor more details about the SET DISPLAY command, see the OpenVMS DCL Dictionary.
To terminate the display, exit the X11 client application, and log out of the SSH session, enter the following command:
$ SET DISPLAY /DELETE