Package ndp
implements the Neighbor Discovery Protocol, as described in
RFC 4861. MIT Licensed.
The command ndp
is a utility for working with the Neighbor Discovery Protocol.
To learn more about NDP, and how to use this package, check out my blog: Network Protocol Breakdown: NDP and Go.
Listen for incoming NDP messages on interface eth0 to one of the interface's global unicast addresses.
$ sudo ndp -i eth0 -a global listen
$ sudo ndp -i eth0 -a 2001:db8::1 listen
Send router solicitations on interface eth0 from the interface's link-local address until a router advertisement is received.
$ sudo ndp -i eth0 -a linklocal rs
Send neighbor solicitations on interface eth0 to a neighbor's link-local address until a neighbor advertisement is received.
$ sudo ndp -i eth0 -a linklocal -t fe80::1 ns
An example of the tool sending a router solicitation and receiving a router advertisement on the WAN interface of a Ubiquiti router:
$ sudo ndp -i eth1 -a linklocal rs
ndp> interface: eth1, link-layer address: 04:18:d6:a1:ce:b8, IPv6 address: fe80::618:d6ff:fea1:ceb8
ndp rs> router solicitation:
- source link-layer address: 04:18:d6:a1:ce:b8
ndp rs> router advertisement from: fe80::201:5cff:fe69:f246:
- hop limit: 0
- flags: [MO]
- preference: 0
- router lifetime: 2h30m0s
- reachable time: 1h0m0s
- retransmit timer: 0s
- options:
- prefix information: 2600:6c4a:7002:100::/64, flags: [], valid: 720h0m0s, preferred: 168h0m0s