Subject Re: [IBO] Events: app freezes when registering events
Author Helen Borrie
At 12:09 PM 13/12/2006, you wrote:
>A customer has been using my app for a few months and today my app
>starts freezing on them. I have madExcept embedded into the program
>and it generates error reports like this:
>exception message : The application seems to be frozen.
>main thread ($304):
>ntdll.dll NtWaitForSingleObject
>ws2_32.dll select
>fbclient.dll gds__alloc
>fbclient.dll _isc_event_block
>nCall.exe IB_Events 782 +18 TIB_Events.API_Register
>fbclient.dll isc_que_events
>nCall.exe IB_Events 803 +8 TIB_Events.API_QueueEvents
>nCall.exe IB_Events 576 +15 TIB_Events.RegisterEvents
>This is happening on all their PCs (8 of them). All report a similar
>error to the above. This has worked fine for the past few months and
>nothing of note has changed.
>Any pointers about where to begin tracking this down?

Should be quite easy. The problem here is that someone has blocked
off all the unused TCP/IP ports on the server. Could be a Windows
update, or could be just a tightening up by the network admin. The
server needs to have at least one open port free and available for
events traffic.

When a request to register events arrives, the server asks for a
TCP/IP port (any will do.) By default, it is just random
ask. However, if the network admin doesn't want to keep say 4 ports
open and allow them to be accessed by the server and the house
clients then you can specifically set aside on using the
RemoteAuxPort parameter in firebird.conf. Of course, this port has
to be open to the LAN and you have to stop and restart the server for
the setting to take effect.