Machines that act as Application Servers for DP4 thin clients should be loaded as DP4 servers using any of the networking configurations with server capabilities. There are no additional components to load on the application server, except that you need to ensure that all the applications you want to run are installed on the server, and you need to enable support for remote execution by specifying the -allow_execute option on the command line for TCPMGR. For security reasons it is a good idea to also specify the -rocopy option at the same time, though this will prevent some DP4 utilities from being run from requester machines. See Secure Operation of DP4 in the Guide to DP4 Configuration for more information about Security.
Thus the [startup] section on the application server might look like this:
[startup]Machines running as any kind of server can act as an application server - the same command tails should be used on the line that loads TCPMGR in the Named Connection Configuration or Multiple Resilience Combined Client/Servers.
The DP4 Thin Client is loaded with the TSTCPx as an additional program to your chosen regular DP4 configuration. You will most likely be using the client only networking configuration, but the thin client is also compatible with the Named Connection configuration and the Local Database Resilience Client.
It does not actually matter where in the sequence this component
is loaded, but it is probably most logical to load it immediately
after the program that provides the application level database
manager. For example, if you are using client only networking you
would use the following:
[startup]
1=tcpw.w32 -server_name servername
2=tstcpw.w32
Refer to How to Load the Named Connection Configuration, for an appropriate [startup] for configuring a machine so that is can act both as an application server and a thin client simultaneously.
On Windows NT,2000,XP if you will be running the DP4 system as a service you must allow the service to interact with the desktop, otherwise the DP4 thin client will not work properly.
The server name specified for tcpw does not prevent you from running applications on more than one application server. It merely establishes a default server. When applications are started you can over-ride the server name.
On Unix and Linux use the following command in a shell or a
shell script:
tstcp3
If you are using 4.525 and dbdaemon use the following additional
command in the [startup] section in dp4.ini.
n=tstcp3
To start an application running on the server the TSRUN program is used. The way to use this program is as follows:
You can also use TSRUN to start an application running completely remotely on the server. In this case add the command tail -remoteonly.
On Windows you can set up short cuts or batch files with the appropriate command lines for programs you want to run using TSRUN. Similarly on Unix you could create a shell script. On Windows CE this is not possible. Therefore from 4.620 TSRUN supports a second method of running programs : if TSRUN is invoked with no arguments at all then it looks for:
[tsrun]in the DP4 configuration file. Unfortunately the command line cannot include command line options for TSRUN, only for the program to be run. In particular you cannot use the -server_name command tail to run programs on another application server. If you need to run more than one program from a TSRUN short cut you can copy TSRUN to another name. In fact TSRUN looks for the command in the section with the name of the currently running executable. This method of running programs also works on regular Windows.
If TSRUN is started with no command line and there is no command entry in the [tsrun] section of the DP4 configuration file, TSRUN will invoke the DP4 program itself.