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The LG GDK phone system sends SMDR information via a serial connection. You need to directly connect a serial cable from the LG GDK phone system to the PC that NetPBX is installed and running on.
As Since the LG GDK doesn't have the SMDR output enabled by default, you need to speak with ask your system maintainer to enable the SMDR logs logging for outgoing, incoming and abandoned calls.
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