Tribon Data Base superserver and subserver

2011/10/16 21:15

The client-server access to a data bank located on a remote machine is based on ONC RPC (Open Network Computing Remote Procedure Calls). In order to provide access to data bank located on the server we must have the following Windows services running on the server machine:

  • PowerRPC Portmapper
  • TRIBON M1 DB Service

TRIBON M1 DB Service is what we call "superserver". Its executable file is - ea312.exe.

This superserver listens to calls from client applications and when the first request to access a data bank arrive, the superserver run another program - ea310.exe which we call "subserver".

On the server machine we may have only one superserver process, but more than one subserver processes. For every application accessing the data banks, we must have one subserver process dedicated to transfer the data between the application and the data banks. When the application is terminated the corresponding subserver process should be automatically stopped. In other words, if you have 10 Tribon applications accessing data bases located somewhere on the server, then you should have one ea312 process and ten ea310 processes running on the server. If you do not have any Tribon application running - you should have only one ea312 process running on the server.

However, it might happens that the data base subserver process is not terminated when the client's application exit. For a period of few hours a small design group (let say 5 - 10 persons) usually generate a number of such obsolete subservers. These obsolete processes could lock some extra licenses, lock or even corrupt the corresponding data bank, decrease the system performance, etc. Hence, we have a pretty good reason to terminate any obsolete Tribon subserver as soon as it appear. There are several ways to do that.

One of them is to use "Tribon DB Server Maint" application. Unfortunately, it is hard to determine there which process is obsolete and which one - not. Using this application any user can kill any Tribon subserver. It is very easy (and it happens quite often) to terminate a working subserver and this way to destroy the corresponding application. Then somebody in the workgroup will get the message "Tribon DB SubServer on host host_name not responding" and his application will not be able neither to save the changes to the data base, neither to read from the data base.

One optional way to deal with the obsolete Tribon subservers is to use the new DBTools Pro version and its Data Base SubServer process control facility. It provide an easy and safety way to clean any obsolete subserver. While DBTools Pro is running on the user's machine, it constantly monitor all subservers and Tribon applications running on the user's PC. If one application exit and its corresponding subserver does not terminate, a message box will inform the user about the obsolete subserver and an option to kill this process will be provided. The users are allowed to kill only those Tribon subservers that belongs to themselves. An Administrator's version is available as well. It has extended functionality and allows also obsolete subsevers clean up at scheduled time interval.