Calin

Probably totally unrelated, but I've had intermittent problems on a
couple of sites both of which turned out to be a problem with client
machines. They had developed problems with their network hardware and
were dropping connections ( 10054 errors ;) ). This should not bother
Firebird, but it was affecting other things and once the problem client
was identified and repaired the problem went away!

You mentioned that TCP/IP connection was lost, which could indicate that
it's the network layer that is getting confused by the problem client
rather than Firebird. It's probably not practical, but I might suggest
putting FB1.5 back just to cross check? Personally I handle upgrades of
this type by additional hardware, leaving the old setup in place in the
background until the new one has been running for a week or so.

--
Lester Caine - G8HFL
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