The NAS maintainer was nice enough to get back to me, and problem has
been sorted out. This is what was happening:
Their proxy servers are behind a load sharing device, which is why the
retransmission of one of the records had a different client_ip_address,
but both entries came from the same NAS-ip-address.
I have removed the client_ip_address from the unique_id declaration, and
made the unique_id column unique in my database, so this should solve
all my problems :]
Thanks so much for your time and help!
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