The Interface Traffic is 400M Higher Cecause no Blackhole Route is Configured on the USG5300

Publication Date:  2012-07-17 Views:  69 Downloads:  0
Issue Description
A carrier reports that the incoming traffic and outgoing traffic of the USG5300 are inconsistent. The gap between the traffic from the NE40 to the USG5300 and the traffic from users to the USG5300 is about 400M.
Alarm Information
Handling Process
Configure a blackhole route to the address pool.  
Root Cause

1.          The connection between the USG5300 and the NE40 use a network segment of a 30-bit mask. The address pool contains three network segments of 28-bit masks.

The nat outbound command is executed on the USG5300. If users on extranet access addresses in the address group, the USG5300 forwards such traffic to the gateway according to the default route. As a result, the egress traffic is heavier than the ingress traffic.