System Administration Guide, Volume 3

snoop(1M)

The snoop command can capture both IPv4 and IPv6 packets. It can display IPv6 headers, IPv6 extension headers, ICMPv6 headers, and neighbor discovery protocol data. By default, the snoop command displays both IPv4 and IPv6 packets. By specifying the ip or ip6 protocol keywords, the snoop command displays only IPv4 or IPv6 packets. The IPv6 filter option enables you to filter through all packets (both IPv4 and IPv6), displaying only the IPv6 packets. See the snoop(1M) man page for details. See "How to Monitor Only IPv6 Network Traffic" for a description of procedures using this command.