Kbase 19285: Error (748) or "Exceeding permissible number of connections"
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
12/1/1999 |
|
SUMMARY: Error (748) or "Exceeding permissible number of connections" during database connection.
This document applies to: Progress Client/Server
Version and Release Number: Progress 9.0 and above
INTRODUCTION:
On version 9.0A and above, progress introduced the SQL-92 engine. This is a robust and reliable SQL interface, which allow the non-4GL clients access a Progress database using SQL-92 standard.
PROCEDURAL APPROACH:
Both 4GL and non-4GL clients will request a database connection to the database broker, depends on the type of client the broker will spawn the appropriate remote server to handle the communication between the client and the database. For 4GL clients the executable name is _MPROSRV, for the other non-4GL clients the name is _SQLSRV2.
They have different purpose and works different too. The _MPROSRV can handle more than one 4GL remote client at a time but the _SQLSRV2 must have one process for each non-4GL client. If you have 50 non-4GL remote clients you will have 50 _SQLSRV2 processes running on the server machine.
On the point of view for the Broker process, both remote servers will be count at the same way. If you are using the -Mn parameter to define the number of remote server for a database you should consider the value of the parameter for both type of server. Using the default parameters for number of users (-n 20) and number of remote server (-Mn 4) when you connect 4 non-4GL clients, the maximum number of remote server allowed for the database is reached and even with -n parameter in 20 you will not be able to connect more remote clients.
4GL client the message: "The server or the system has no more resources. Try a larger -n. (748)" will appear.
Non-4GL client the message: "Exceeding permissible number of connections" will appear on the ODBC client.
Database log file:
09:25:47 BROKER 0: No servers are available. Try again later. (1154)
09:25:57 BROKER 0: No SQL servers are available. Try again later. (8839)
To avoid this situation, keep in mind the maximum number of remote clients (4GL and non-4GL) during the configuration of -Mn parameter on the database.