Subject FB 1.5 Connection lost problem
Author dirknaudts

I'm setting up up a project on a customer's Server (Redhat Advanced
Server 2.1 on Compaq Proliant Server), FB1.5 SS

I'm developing using D7 Ent, and I was using IBO 4.2Ha to connect to
the db, but after having revisiting Jason's site, I noticed I was
behind on updates, and downloaded 4.3Aa (Trial, subscription to
source updates expired) and recompiled with that one.

I've added Ib_constants as the first unit in the uses clause of my
datamodule, and added an initialization section

IB_CONSTANTS.IB_GDS32 := 'fbclient.dll';

furthermore I put fbclient.dll in a resource file, so that I can save
it to app-current dir when not already there. (This way I can still
have a no-setup-needed application)

The reason I went looking for an IBO update was the following :

ISC ERROR CODE:335544721

Unable to complete network request to host "".
Error writing data to the connection.
An established connection was aborted by the software in your host

This error only occurs after having been connected for some time
(sometimes minutes, sometimes hours) so in the beginning all apps are
working fine.
Since I'm connected with several (different) apps at the same time
(from different client machines,both xp and 2k) I noticed that it's
not a general problem, meaning app1-pc1 might get the problem,
whereas app1-pc2, app2-pc3 and app3-pc4 are still connected. So it
doensn't seem to be a network (hardware), nor application related

I also use tbudf.pas, compiled using Kylix3 to have udf support on
the server.

Now I'm puzzled as to what is causing this problem, is it sth on the
server machine, is it FB Server, fbclient, or IBO ?

btw, do I need to buy the IBO update (4.2Ha -> 4.3Aa) or should I be
ok with version 4.2Ha to connect to FB1.5 (I'm not using events) ?

any hints are very welcome,


Dirk Naudts
ATS Belgium.