Hello Olaf,

> Hello,
>
> I plan an update of firebird 2.1 cs 32 Bit with 32 Bit Server OS to
> Firebird 2.5. Is there a 64 Bit OS recommend and a 64 Bit installation
> of Firebird too?

From an operational POV, a main factor with moving from 32-bit to
64-bit is if you are using (third-party) UDF libraries. You need them to
be compiled with a 64-bit compiler if you want to run Firebird 64-bit.

Other than that, I guess it depends on your planned load, especially
addressable RAM by the Firebird server process. If still intend to run
with ClassicServer, then each connection spawns its own process, thus
you probably won't hit the addressable RAM limit with Firebird 32-bit.
That might be different with Firebird SuperClassic (32-bit), because
this is a single process architecture.

I connect with odbc. Known Issues while migration,

> metadata etc. ?

The usual path is creating a gbak-based backup with Firebird 2.1 and
restore it under Firebird 2.5. The resulting ODS will be 11.2 (you can
check with gstat -h afterwards).

On the client side, make sure that you are using a version of the
Firebird client library matching the server version. Bitness (32-bit vs.
64-bit) of the client library is driven by your application and not by
the Firebird server. So, if you are application is 32-bit (Delphi
32-bit?) use a Firebird 32-bit client library and ODBC driver.

Hope this helps.

--
With regards,
Thomas Steinmaurer
http://www.upscene.com/

Professional Tools and Services for Firebird
FB TraceManager, IB LogManager, Database Health Check, Tuning etc.