Subject Re: [firebird-support] connection ! problem - centos 4.3, have tested with all versions of 1.5.3
Author Helen Borrie
At 12:46 AM 4/10/2006, you wrote:
>Dear group
>I am connecting using from a windows XP SP2 workstation which
>simultaneously accesses two databases on a centos 4.3 server
>(, with the following lines in the .ini file of a
>proprietary windows program:
>I can connect to, and view, each of these two databases (mIBDB and
>mimsIBDB) on the home network here using a firebird gui program, but
>when I try to connect using the proprietary program I get the
>message 'cannot connect to mimsIBDB' and the app doesn't run. The
>anomaly is that I can connect using this same windows application, to
>the *same* databases on a remote computer, via port 3050 (this was an
>experiment). I think 1.5.1 is running remotely, but I'm not sure how
>to determine the version. mIBDB and mimsIBDB were gbak'd and restored
>here at home, from the remote location. File and dir permissions here
>at home are exactly the same as remotely.
>When I try to do the opposite, i.e. connect from the remote location
>(windows xp sp2) to the home server via 3050 - you guessed it - the
>message is 'cannot connect to mimsIBDB'.
>Thirdly, if I configure the workstation to connect to mIBDB locally
>and the remote version of mimsIBDB, the app will run.
>The company that provides the databases can't figure out why. I don't
>want to reinstall the OS but am running out of options.
>Could it be something in firebird.conf? Firebird.log does not contain
>anything helpful
>The relevant entries in windows 'services' and 'hosts' files have been
>added for the proprietary program.
>I tried installing the nptl version and the SS versions, and currently
>have the CS versions but none work. Have tried rpm installs and
>some .tar installs.
>The kernel is 2.6.9-34.0.2.EL-i686 (am not using the smp kernel)
>If there is a simple fix, or something worth trying, would be very
>interested. Does anyone have 1.5.1 ?

I think you have several issues/misconceptions here.

The first one to look at is the one of reading a static connection
string from an ini file and expecting it to "just work" on any
network. The IP address is a restricted one that will
work ONLY within a Class C LAN and then only if there is a host
broadcasting that address within that LAN.

The overriding problem, from a troubleshooting point of view, is that
you are not reporting any exception messages that one could deduce
anything about. The one error message you tell us about is generated
by your application, not by Firebird or InterBase. Apparently your
application code is merely "eating" all exceptions from the database
server/client interface and blatting them out as "cannot
connect". No doubt you can understand how unhelpful this is.

I suggest that you try to repeat your tests using a tool that returns
the actual exception messages. The command-line utility isql will do
that, or you could download ib_sql from (To copy
output from the Windows command shell window, highlight the text with
your mouse and press Enter. You can then paste it into an email or
other file...)

You say there is "nothing useful" in the log. Could you post the
"non-useful" entries that appear after your connection failures? If
you inspect the log in a console window that you opened from your
Centos GUI, you will be able to copy from it.

Another thing I can't work out is how you "connect locally" from your
Windows application to a database running on a Linux host. Could you
explain more exactly how you do that, e.g. are you running the
Windows app in a wine server or other Windows emulator?