libxt_TEE.man

The \fBTEE\fP target will clone a packet and redirect this clone to another
machine on the \fBlocal\fP network segment. In other words, the nexthop
must be the target, or you will have to configure the nexthop to forward it
further if so desired.
.TP
\fB\-\-gateway\fP \fIipaddr\fP
Send the cloned packet to the host reachable at the given IP address.
Use of 0.0.0.0 (for IPv4 packets) or :: (IPv6) is invalid.
.PP
To forward all incoming traffic on eth0 to an Network Layer logging box:
.PP
\-t mangle \-A PREROUTING \-i eth0 \-j TEE \-\-gateway 2001:db8::1