8.6.3.Initial Connection Problems
The OpenLink Database Agent for Progress is a Hybrid of OpenLink & Progress ESQL/C components, indicating that the actual OpenLink Database Agent for Progress is for all intents and purposes a Progress ESQL/C client.
The files "proxxx_sv" or "proxx_sv.exe" are your OpenLink Database Agent for Progress executables (note: xxx represents Progress major and minor release numbers e.g. Progress 7.3C would be represented as pro73c_sv). These files are always situated in the "bin" sub-directory of your OpenLink installation directory.
When you attempt to make an ODBC/JDBC/UDBC connection to your Progress Database Engine(s), and you encounter a problem, one of the following error conditions would typically be presented to you via your ODBC/JDBC/UDBC application:
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"There is no server this database you are attempting to connect with", even though you know there is a server running for that database.
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"Shared memory of a particular version was expected, but shared memory of another version has been found"
The conditions above arise due to the fact that the OpenLink Database Agent for Progress not being built using Progress ESQL/C libraries that do not match your Progress Database Server to the exact minor release. This is to say that although the OpenLink Database Agent for Progress may have been built using ESQL/C libraries for Progress 7.3A, you will still have a version incompatibility problem of this nature should you attempt to connect this ESQL/C client to a Progress 7.3C Database Server process.
This error condition arises as a result of the fact that the OpenLink Database Agent for Progress defaults to using Shared Memory for its Inter Process Communications (IPC) , and that Shared Memory is very version sensitive nature albeit the fastest IPC mechanism .
There are two possible ways to work around this situation when it arises.
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Change the default IPC mechanism of the OpenLink Database Agent for Progress, from Shared Memory to TCP sockets, as TCP sockets based IPC is version sensitive.
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Rebuild/Relink your OpenLink Database Agent for Progress, achieved by running an OpenLink provided link script that produces a new OpenLink Database Agent for Progress executable with an exact Shared Memory match for your Progress Database Server.