Applies To:
  • CitectSCADA x.x

How do I setup Citect to run across the Internet? 

First thing to keep in mind is that the Internet is no different from any other TCP/IP Network except that it is bigger.

Imagine that we have Citect Server located in Sydney, Australia (IP address: and that we want to connect to it with a Display Client in New York (IP address: When the Display Client starts up you will see in the startup popup dialog how Citect is "Calling 'IOServer' ", "Calling CitectTrend", "Calling CitectAlarm" and finally "Calling CitectReport". What actually happens now is that Citect tries to establish a direct contact with the server but this will fail as NetBIOS will try to do a broadcast and only TCP/IP does not allow NetBIOS to make a broadcast on the Internet. Therefore we have to help TCP/IP find the Citect server without doing a broadcast on the network. This is done by a LMHOSTS file. This file has a simple structure which enables TCP/IP to look up a computer name and get its IP-address to establish a connection. The structure of the LMHOSTS file is as follows:

<IP-address> <computer name> #PRE

To setup the above example follow these steps:

  1. Setup the Sydney server with the Computer Setup Tool as a Networked Server and Display Client and the Display Client in new York as a Networked Display Client.  If the Display Client is located in a region that uses Display Client licences such as the USA then manually change the parameter [CLIENT]Display=1.
  2. Make sure that the Citect server can be reached from the Display Client with the PING command. Type PING (exchange this address for your server address) from the MS-DOS prompt on the Display Client. If you get no response you have to check your Internet connection from both your computers.
  3. Edit the LMHOSTS file on the Display Client.

In our above example the Display Clients LMHOSTS file should look as follows: IOServer #PRE CitectAlarm #PRE CitectTrend #PRE CitectReport #PRE

Use a text editor to create a file as above or edit the default file called LMHOSTS.SAM and save it as LMHOSTS (note! the name of the file is LMHOSTS. with no extension).

The LMHOSTS file resides:
Window95: \WINDOWS

  1. Modify Citect.ini file on the display client as follows:

    under [lan] add these two lines NetBIOS=0; TCPIP=1.

    Under [DNS] add or change this line primary=, to Primary =aaa.bbb.ccc.ddd

    (the IP address of server)

  2. Then modify Citect.ini file on the server as follows:

    under [lan] add TCPIP=1.

  3. Restart your Display Client and make sure you are connected to the Internet.
  4. Start up your application on the Display Client. You should now see how the Client connects to the server across the Internet