• View
• Edit
• History
• Print

Using TurboVNC with the UltraVNC Repeater

Installing the UltraVNC Repeater

As root ...

1. Obtain the source tarball from here.
2. Untar it.
3. cd uvncrep017ws
4. make install
5. useradd -d /etc/uvnc -s /sbin/nologin uvncrep
6. Edit /etc/uvnc/uvncrepeater.ini, changing viewerport to 5900. Make any other edits you feel are necessary to this file, including restricting the allowed modes and (if you are using Mode II) specifying the allowed IDs.
7. service uvncrepeater start

NOTE: This is known to work with RHEL/CentOS 5-7. It will probably not work in a pure systemd environment, unless it has backward compatibility with SysVinit.

Mode I

Referring to the diagrams on this page, the UltraVNC Repeater in Mode I acts as a gateway between VNC viewers and VNC servers. Usually the VNC servers are on a walled-off "server-area network" (SAN), and the gateway serves as a bridge between that closed network and a local-area network (LAN) or wide-area network (WAN.) The viewers connect to the UltraVNC Repeater through the LAN/WAN, and the repeater accepts a string that tells it to which VNC server on the SAN it should connect a particular viewer. In TurboVNC, this is implemented with the "Via" parameter in the Java TurboVNC Viewer (our Windows native viewer does not yet support UltraVNC Repeater connections.)

Mode I Connection Procedure

1. Build, install, and start the UltraVNC Repeater on the gateway machine (see above.)
2. If the gateway machine has a firewall, make sure that port 5900 is open.
3. Start a TurboVNC Server session on one of the VNC server machines.
4. Start the Linux, Mac, or Windows Java TurboVNC Viewer on the client machine.
5. Open the Options dialog in the TurboVNC Viewer. Under the "Security" tab, in the "Host" field, enter the hostname or IP address of the gateway machine and the VNC display number or IP port on which the UltraVNC Repeater is listening (for instance, "my_gateway_machine:0" or "my_gateway_machine::5900".)
6. Click OK to dismiss the Options dialog, then enter the hostname/IP address and VNC display number/port for the VNC server to which you want to connect (for instance, "my_vnc_server:1" or "my_vnc_server::5901") in the "VNC server" field. Click "Connect".
   NOTE: the hostname/IP address of the VNC server machine should be specified from the point of view of the gateway/repeater machine. Thus, if the TurboVNC Server session is running on the same machine as the UltraVNC Repeater, then the VNC server hostname would be "localhost".

You can also do this entirely using Java parameters, which can be passed on the command line or with Java Web Start. The "Via" parameter specifies the gateway hostname/IP address + repeater display number/port, and the "Server" parameter specifies the VNC server hostname/IP address + display number/port (from the gateway's point of view.)

This is, incidentally, very similar to the procedure for SSH tunneling with the TurboVNC Viewer, which is documented in the User's Guide. The only difference is that, with SSH tunneling, a display number/port is not specified for the gateway machine. The TurboVNC Viewer assumes that, if the "Via" parameter does not contain a display number/port, then it should connect to an SSH server rather than an UltraVNC Repeater.

Mode II

Referring to the diagrams on this page, in Mode II, the UltraVNC Repeater and the VNC server(s) and the VNC viewer(s) are all located on the same open network. This architecture is similar in concept to GoToMeeting, in that the UltraVNC Repeater acts as a central dispatcher rather than a gateway, and both the viewers and servers make outbound connections to it. In TurboVNC, this is accomplished using the "reverse connection" feature in the TurboVNC Server.

Mode II Connection Procedure

1. Build, install, and start the UltraVNC Repeater on the dispatch machine (see above.)
2. If the dispatch machine has a firewall, make sure that ports 5500 and 5900 are open.
3. Start a TurboVNC Server session on one of the VNC server machines.
4. On the same machine, initiate an outbound connection to the UltraVNC Repeater by using the vncconnect command:
   
   

   /opt/TurboVNC/bin/vncconnect -display {my_vnc_display_number} -id {unique_session_id} {my_dispatch_machine}
   

   
   where {my_vnc_display_number} is the VNC display number of the TurboVNC Server session you just started (for example, ":1"), {my_dispatch_machine} is the hostname or IP address of the machine on which the UltraVNC Repeater is running, and {unique_session_id} is a unique ID for this TurboVNC Server session (that ID should have previously been added to the list of allowed IDs on the dispatch machine. See above.)
5. Start the Linux, Mac, or Windows Java TurboVNC Viewer on the client machine.
6. Open the Options dialog in the TurboVNC Viewer. Under the "Security" tab, in the "Host" field, enter the hostname or IP address of the dispatch machine and the VNC display number or IP port on which the UltraVNC Repeater is listening (for instance, "my_dispatch_machine:0" or "my_dispatch_machine::5900".)
7. Click OK to dismiss the Options dialog, then enter ID:{unique_session_id} in the "VNC server" field, where {unique_session_id} is the session ID you chose above. Click "Connect".

You can also do this entirely using Java parameters, which can be passed on the command line or with Java Web Start. The "Via" parameter specifies the dispatch hostname/IP address + repeater display number/port, and the "Server" parameter specifies the session ID (preceded by "ID:".)