| No. | Title | Result | Log | Script | Packet | Dump (bin) |
Dump (txt) |
|---|---|---|---|---|---|---|---|
| 3 | DAD Success when NUT received no packet on Stateless Link-local address autoconfiguration | FAIL | X | X | X | Link0 | Link0 |
RFC 2461 Neighbor Discovery for IPv6
7.2.3. Receipt of Neighbor Solicitations
A valid Neighbor Solicitation that does not meet any the following
requirements MUST be silently discarded:
- The Target Address is a "valid" unicast or anycast address
assigned to the receiving interface [ADDRCONF],
- The Target Address is a unicast address for which the node is
offering proxy service, or
- The Target Address is a "tentative" address on which Duplicate
Address Detection is being performed [ADDRCONF].
If the Target Address is tentative, the Neighbor Solicitation should
be processed as described in [ADDRCONF]. Otherwise, the following
description applies. If the Source Address is not the unspecified
address and, on link layers that have addresses, the solicitation
includes a Source Link-Layer Address option, then the recipient
SHOULD create or update the Neighbor Cache entry for the IP Source
Address of the solicitation. If an entry does not already exist, the
node SHOULD create a new one and set its reachability state to STALE
as specified in Section 7.3.3. If an entry already exists, and the
cached link-layer address differs from the one in the received Source
Link-Layer option, the cached address should be replaced by the
received address and the entry's reachability state MUST be set to
STALE.
If a Neighbor Cache entry is created the IsRouter flag SHOULD be set
to FALSE. This will be the case even if the Neighbor Solicitation is
sent by a router since the Neighbor Solicitation messages do not
contain an indication of whether or not the sender is a router. In
the event that the sender is a router, subsequent Neighbor
Advertisement or Router Advertisement messages will set the correct
IsRouter value. If a Neighbor Cache entry already exists its
IsRouter flag MUST NOT be modified.
If the Source Address is the unspecified address the node MUST NOT
create or update the Neighbor Cache entry.
After any updates to the Neighbor Cache, the node sends a Neighbor
Advertisement response as described in the next section.
7.2.4. Sending Solicited Neighbor Advertisements
A node sends a Neighbor Advertisement in response to a valid Neighbor
Solicitation targeting one of the node's assigned addresses. The
Target Address of the advertisement is copied from the Target Address
of the solicitation. If the solicitation's IP Destination Address is
not a multicast address, the Target Link-Layer Address option MAY be
omitted; the neighboring node's cached value must already be current
in order for the solicitation to have been received. If the
solicitation's IP Destination Address is a multicast address, the
Target Link-Layer option MUST be included in the advertisement.
Furthermore, if the node is a router, it MUST set the Router flag to
one; otherwise it MUST set the flag to zero.
If the Target Address is either an anycast address or a unicast
address for which the node is providing proxy service, or the Target
Link-Layer Address option is not included, the Override flag SHOULD
be set to zero. Otherwise, the Override flag SHOULD be set to one.
Proper setting of the Override flag ensures that nodes give
preference to non-proxy advertisements, even when received after
proxy advertisements, and also ensures that the first advertisement
for an anycast address "wins".
If the source of the solicitation is the unspecified address, the
node MUST set the Solicited flag to zero and multicast the
advertisement to the all-nodes address. Otherwise, the node MUST set
the Solicited flag to one and unicast the advertisement to the Source
Address of the solicitation.
If the Target Address is an anycast address the sender SHOULD delay
sending a response for a random time between 0 and
MAX_ANYCAST_DELAY_TIME seconds.
Because unicast Neighbor Solicitations are not required to include a
Source Link-Layer Address, it is possible that a node sending a
solicited Neighbor Advertisement does not have a corresponding link-
layer address for its neighbor in its Neighbor Cache. In such
situations, a node will first have to use Neighbor Discovery to
determine the link-layer address of its neighbor (i.e, send out a
multicast Neighbor Solicitation).