After you configure log forwarding to Log Collectors, managed firewalls open a TCP connection to
all configured Log Collectors. These connections timeout every sixty (60) seconds
and do not indicate that the firewall has lost connection to the Log Collectors.
When you configure log forwarding to a local or Dedicated Log Collector over a
supported ethernet interface, the firewall traffic logs show
incomplete sessions despite the firewall being able
to successfully connect to the Log Collectors. If you configure log forwarding over
the management port, no traffic logs showing incomplete
sessions are generated. Traffic logs showing incomplete
sessions are generated by all firewalls except for the PA-5200 and PA-7000 series
firewalls.