> When I'm using a monitor of the Firebird tables, there's even refuse new connections, it does not always happen.
>
> What could be?

Possibly a bug. What Firebird architecture and version?

Perhaps this one does apply to you ...
http://tracker.firebirdsql.org/browse/CORE-2209



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Thomas Steinmaurer
LogManager Series - Logging/Auditing Suites supporting
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Upscene Productions
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