The PCA automatically configures its listen filters to allow 802.1q VLAN packets to be captured without explicit configuration.
If you are using
tcpdump for traffic analysis, you must manually apply the VLAN
filter tags at the command line to see VLAN packets. In the previous section, the command to start
tcpdump must be augmented to enable VLAN packet capture in the following manner:
tcpdump -n -i eth0 "((host 127.0.0.1 and port 80) or \ (host 172.16.0.1 and port 1) or (host 172.16.0.2 and port 2) or \ (vlan and host 127.0.0.1 and port 80) or \ (vlan and host 172.16.0.1 and port 1) or (vlan and host 172.16.0.2 and \ port 2))"