RRAdvertisedStatusCode.seq - Requesting Router has received advertise message with Status Code option NoPrefixAvail
Router for DHCP client
RRAdvertisedStatusCode.seq [-tooloption ...] -pkt RRAdvertisedStatusCode.def -tooloption : v6eval tool option
TN TN1
| | ISP site
--+----+-------+------- Link0
|
NUT Host
| | Customer site
-------+-------+------- Link1 3ffe:501:fffc:XXXX::/64
| TN |
Link-local |
fe80::200:ff:fe00:a0a0 |
| Ether |
00:00:00:00:a0:a0 |
| Delegate Prefix |
3ffe:501:fffc:: |
| Prefix Length |
48 |
| TN1 (other server) |
Link-local |
fe80::200:ff:fe00:a1a1 |
| Ether |
00:00:00:00:a1:a1 |
| Delegate Prefix |
3ffe:501:fffc:: |
| Prefix Length |
48 |
| Host |
Link-local |
fe80::200:ff:fe00:101 |
| ether |
00:00:00:00:01:01 |
- NUT sets up Prefix Delegation.
Tester as Server Target as Client Tester as Host
| | |
|<--------------------------| |
| DHCP Solicit message | |
| | |
1. Wait DHCP Solicit message
Addresse
Solicit messages
| Src |
NUT link-local address |
| Dst |
All_DHCP_Relay_Agents_and_Servers |
All_DHCP_Relay_Agents_and_Servers FF02::1:2
UDP Ports
Clients listen for DHCP messages on UDP port 546
Server listen for DHCP messages on UDP port 547
DHCP Message
DHCP Solicit message
| msg-type |
SOLICIT(1) |
| transaction-id |
The transaction ID for this message exchange |
| options |
| Client Identifier Option (MUST) |
| IA_PD Option (MUST) |
| |
Code |
33 (TBD) |
| |
IAID |
The unique identifier which client specified |
| |
T1 |
ANY |
| |
T2 |
ANY |
| Elapsed Time Option (MUST) |
| |
elapsed-time |
ANY |
| Option Request Option (Optional) |
Tester as Server Target as Client Tester as Host
| | |
|-------------------------->| |
| DHCP Advertise message | |
| w/ Status Code option | |
| NoPrefixAvail | |
| | |
|<--------------------------| |
| Judgment #1 | |
| DHCP Solicit message | |
| | |
|-------------------------->| |
| DHCP Advertise message | |
| from other server | |
| | |
|<--------------------------| |
| Judgment #2 | |
| DHCP Request message | |
| to other server | |
| | |
|-------------------------->| |
| DHCP Reply message | |
| from other server | |
| | |
v v v
1. Send DHCP Advertise message with Status Code option NoPrefixAvail
2. Wait DHCP Solicit message again
3. Send DHCP Advertise message from other server
4. Wait DHCP Request message sending to other server
5. Send DHCP Reply message from other server
Addresses
Solicit, Request messages
| Src |
NUT link-local address |
| Dst |
All_DHCP_Relay_Agents_and_Servers |
All_DHCP_Relay_Agents_and_Servers FF02::1:2
Advertise message
| Src |
fe80::200:ff:fe00:a0a0 |
| Dst |
NUT link-local address |
Advertise, Reply message from other server
| Src |
fe80::200:ff:fe00:a1a1 |
| Dst |
NUT link-local address |
UDP Ports
Clients listen for DHCP messages on UDP port 546
Server listen for DHCP messages on UDP port 547
DHCP Messages
DHCP Advertise message with Status Code option including NoPrefixAvail
| msg-type |
ADVERTISE(2) |
| transaction-id |
The same transaction ID previous message |
| options |
| Client Identifier Option |
| Server Identifier Option |
| |
DUID Contents type |
1 Link-layer address plus time |
| |
hardware type |
1 Ether |
| |
time |
Time which the server included |
| |
link-layer address |
00:00:00:00:a0:a0 |
| Status Code Option |
| |
status-code |
6 NoPrefixAvail (TBD) |
| |
status-message |
0x56, 0x56, 0x56, 0x56, 0x56, 0x56, 0x56, 0x56 |
DHCP Solicit message
Same above
DHCP Advertise message from other server
| msg-type |
ADVERTISE(2) |
| transaction-id |
The same transaction ID previous message |
| options |
| Client Identifier Option |
| Server Identifier Option |
| |
DUID Contents type |
1 Link-layer address plus time |
| |
hardware type |
1 Ether |
| |
time |
Time which the server included |
| |
link-layer address |
00:00:00:00:a1:a1 |
| Preference Option |
| |
pref-value |
255 |
| IA_PD Option |
| |
Code |
33 (TBD) |
| |
IAID |
Unique identifier which client specified |
| |
T1 |
300 |
| |
T2 |
480 |
| |
IA_PD Prefix Option |
| |
|
Code |
34 (TBD) |
| |
|
preferred-lifetime |
600 |
| |
|
valid-lifetime |
1200 |
| |
|
prefix-length |
48 |
| |
|
IPv6 prefix |
3ffe:501:fffc:: |
DHCP Request message to other server
| msg-type |
REQUEST(3) |
| transaction-id |
The transaction ID for this message exchange |
| options |
| Client Identifier Option (MUST) |
| Server Identifier Option (MUST) |
| |
DUID Contents type |
1 Link-layer address plus time |
| |
hardware type |
1 Ether |
| |
time |
Time which the server included |
| |
link-layer address |
00:00:00:00:a1:a1 |
| IA_PD Option (MUST) |
| |
Code |
33 (TBD) |
| |
IAID |
Unique identifier which client specified |
| |
T1 |
ANY |
| |
T2 |
ANY |
| |
IA_PD Prefix Option (Optional) |
| |
|
Code |
34 (TBD) |
| |
|
preferred-lifetime |
ANY |
| |
|
valid-lifetime |
ANY |
| |
|
prefix-length |
48 |
| |
|
IPv6 prefix |
3ffe:501:fffc:: |
| Elapsed Time Option (MUST) |
| |
elapsed-time |
ANY |
| Option Request Option (Optional) |
DHCP Reply message from other server
| msg-type |
REPLY(7) |
| transaction-id |
The same transaction ID previous message |
| options |
| Client Identifier Option |
| Server Identifier Option |
| |
DUID Contents type |
1 Link-layer address plus time |
| |
hardware type |
1 Ether |
| |
time |
Time which the server included |
| |
link-layer address |
00:00:00:00:a1:a1 |
| IA_PD Option |
| |
Code |
33 (TBD) |
| |
IAID |
Unique identifier which client specified |
| |
T1 |
300 |
| |
T2 |
480 |
| |
IA_PD Prefix Option |
| |
|
Code |
34 (TBD) |
| |
|
preferred-lifetime |
600 |
| |
|
valid-lifetime |
1200 |
| |
|
prefix-length |
48 |
| |
|
IPv6 prefix |
3ffe:501:fffc:: |
1. NUT ignore DHCP Advertise message with Status Code option NoPrefixAvail. DHCP Solicit message is recieved again.
2. DHCP Request message is recieved sending to other server.
N/A
draft-ietf-dhc-dhcpv6-opt-prefix-delegation-01.txt
10. Delegating Router Solicitation
10.1 Requesting router behaviour
The requesting router creates and transmits a Solicit message as
described in sections "Creation of Solicit Messages" and
"Transmission of Solicit Messages" of the DHCP specification [6].
The requesting router creates an IA_PD and assigns it an IAID. The
requesting router MUST include the IA_PD option in the Solicit
message.
The requesting router processes any received Advertise messages as
described in section "Receipt of Advertise Messages" in the DHCP
specification [6]. The requesting router MAY choose to consider the
presence of advertised prefixes in its decision about which
delegating router to respond to.
The requesting router MUST ignore any Advertise message that includes
a Status Code option containing the value NoPrefixAvail, with the
exception that the requesting router MAY display the associated
status message to the user.
15. IANA Considerations
IANA is requested to assign option codes to these options from the
option-code space as defined in section "DHCPv6 Options" of the
DHCPv6 specification [6].
IANA is requested to assign a status code to the NoPrefixAvail status
code from the status-code space as defined in section "Status Codes"
of the DHCPv6 specification [6].
draft-ietf-dhc-dhcpv6-28.txt
17. DHCP Server Solicitation
17.1. Client Behavior
17.1.3. Receipt of Advertise Messages
The client MUST ignore any Advertise message that includes a Status
Code option containing the value NoAddrsAvail, with the exception
that the client MAY display the associated status message to the
user.
Upon receipt of one or more valid Advertise messages, the client
selects one or more Advertise messages based upon the following
criteria.
- Those Advertise messages with the highest server preference value
are preferred over all other Advertise messages.
- Within a group of Advertise messages with the same server
preference value, a client MAY select those servers whose
Advertise messages advertise information of interest to the
client. For example, the client may choose a server that
returned an advertisement with configuration options of interest
to the client.
- The client MAY choose a less-preferred server if that server has
a better set of advertised parameters, such as the available
addresses advertised in IAs.
Once a client has selected Advertise message(s), the client will
typically store information about each server, such as server
preference value, addresses advertised, when the advertisement was
received, and so on.
If the client needs to select an alternate server in the case that a
chosen server does not respond, the client chooses the next server
according to the criteria given above.
A. Appearance of Options in Message Types
The following table indicates with a "*" the options are allowed in
each DHCP message type:
Client Server IA_NA Option Pref Time Relay Auth. Server
ID ID IA_TA Request Msg. Unica.
Solicit * * * * *
Advert. * * * * * *
Request * * * * * *
Reply * * * * * * *
Status Rap. User Vendor Vendor Inter. Recon. Recon.
Code Comm. Class Class Spec. ID Msg. Accept
Solicit * * * * *
Advert. * * * * *
Request * * * *
Reply * * * * * *
perldoc V6evalTool