The answer to this largely depends on the application you are using and how errors are reported by it. A connection based license slot is consumed when an ODBC application allocates a database handle and calls SQLConnect/SQLDriverConnect. If you exceed the connection limit the Easysoft product which first detects this problem will add a message such as "no license slots available" which may be obtained by a call to SQLGetDiagRec or SQLError (in the usual way). If you are writing the ODBC application you should always ensure that errors returned from an ODBC API are trapped and reported. If the application is outside your control and does not retrieve and show the error you can run the License Manager (MS Windows) or licshell (UNIX) programs to view your licenses. This will indicate if any licenses have expired but unfortunately does not currently show the licenses in use.
The ODBC-ODBC Bridge HTTP Server statistics web page shows the number of concurrent connections. You can use this to see how many concurrent connections to the server are active.
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