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Flow Output
For each flow observed by "conntrack", three flow records are output by
this tool. As explained below, three records are required to correlate
the NAT operation which took place. The assumption of source IP NAT will
be relaxed in a future release of this software.
The format of these lines is "flow-tools" CSV for NetFlow version 5. Of
course your NetFlow collector receives a proper UDP NetFlow payload, but
here we are looking at the default Syslog output. The fields are listed
in order in the table below: