NAME

        SV_RFC1034_3_6_MX_rdata - Resource record of MX

VERIFICATION POINTS

        Verify that a NUT transmits correct message including MX resource record.

A <domain-name> have single MX resource record case.

Header section field has the following value.

QR : 1

QDCOUNT : 1

ANCOUNT : 1

A <domain-name> will have multiple MX resource records.

Header section field has the following value.

QR : 1

QDCOUNT : 1

ANCOUNT : 2

MX RDATA format

+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|                  PREFERENCE                   |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/                   EXCHANGE                    /
/                                               /
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

PREFERENCE :	A 16 bit integer which specifies the preference given to this RR among others at the same owner. Lower values are preferred.
EXCHANGE :	A <domain-name> which specifies a host willing to act as a mail exchange for the owner name.

TARGET

        Authoritative Server

SYNOPSIS

	SV_RFC1034_3_6_MX_rdata.seq [-tooloption ...]: KOI tool option
	See also DNSConfig.pm

INITIALIZATION

Network Topology

        AP Server1 (TN)
          |3ffe:501:ffff:101::10
          |192.168.1.10
          |
Net-y   --+--------+-------------------------- 3ffe:501:ffff:101::/64 
                   |                           192.168.1/24
                   |
                   |
                 Router (TN)
                   |3ffe:501:ffff:100::1
                   |192.168.0.1
                   |
                   |
Net-z   --+--------+-----------------+-------- 3ffe:501:ffff:100::/64 
          |                          |          192.168.0/24
          |                          |
        DNS Server1 (NUT)            DNS Client1 (TN)
           3ffe:501:ffff:100::XXXX     3ffe:501:ffff:100::20 
           192.168.0.10                192.168.0.20
	

	XXXX: EUI64

Setup

Set the DNS Server1's (NUT) address as above mentioned Network Topology.

Configure the Server1's (NUT) zone file to response query from TN.

A. Example of example.com zone file:

$TTL    86400           ; TTL of 1 day
@ IN SOA NS1.example.com. root.example.com. (
	2005081600	; serial
	3600		; refresh every 1 hr
	900		; retry every 15 min
	604800		; expire after a week
	3600		; Minimum TTL of a 1 hr
)
;
	IN	NS	NS1.example.com.
	IN	MX	10	MAIL1
;
NS1	IN	A	192.168.0.10
MAIL1	IN	A	192.168.1.11

B. Example of example.com zone file:

$TTL    86400           ; TTL of 1 day
@ IN SOA NS1.example.com. root.example.com. (
	2005081601	; serial
	3600		; refresh every 1 hr
	900		; retry every 15 min
	604800		; expire after a week
	3600		; Minimum TTL of a 1 hr
)
;
	IN	NS	NS1.example.com.
	IN	MX	10	MAIL1
	IN	MX	20	MAIL2
;
NS1	IN	A	192.168.0.10
MAIL1	IN	A	192.168.1.11
MAIL2	IN	A	192.168.1.12

TEST PROCEDURE

        This test sequence is following.

    DNS Client1 (TN)                       DNS Server1 (NUT)
        |                                      |
        |------------------------------------->|
        |   1. Send standard query             |
        |       QNAME=example.com              |
        |       QTYPE=MX                       |
        |                                      |
        |<-------------------------------------|
        |   2. Standard query response         |
        |       MX=10 MAIL1.example.com        |
        |                                      |
        |(Change zone file on DNS Server1(NUT) |
        |       from A to B.)                  |
        |                                      |
        |------------------------------------->|
        |   3. Send standard query to NUT      |
        |       QNAME=example.com              |
        |       QTYPE=MX                       |
        |                                      |
        |<-------------------------------------|
        |   4. Standard query response         |
        |       MX=10 MAIL1.example.com        |
        |       MX=20 MAIL2.example.com        |
        |                                      |
        v                                      v

        1. TN send standard query QNAME=example.com, QTYPE=MX to NUT.
        2. NUT reply query response w/ MX=10 MAIL1.example.com to TN (Judgment *2)
        3. TN send standard query QNAME=mail.example.com, QTYPE=MX to NUT.
        4. NUT reply query response w/ MX=10 MAIL1.example.com and MX=20 MAIL2.example.com to TN (Judgment *4)

Packet Description

1st packet.

Standard query from DNS Client1 (TN) to Server1 (NUT)
IP Header	Source Address	CL1_NETZ
IP Header	Destination Address	NUT_NETZ
UDP Header	Src Port	2000
UDP Header	Dst Port	53
DNS Header	ID	0x1000
	QR	0
	OPCODE	0
	AA	0
	TC	0
	RD	1
	RA	0
	Z	0
	RCODE	0
	QDCOUNT	1
	ANCOUNT	0
	NSCOUNT	0
	ARCOUNT	0
DNS Question section	QNAME	example.com
	QTYPE	MX (0x000F)
	QCLASS	IN (0x0001)

2nd packet.

Standard query response from DNS Server1 (NUT) to Client1 (TN)
IP Header	Source Address	NUT_NETZ
IP Header	Destination Address	CL1_NETZ
UDP Header	Src Port	53
UDP Header	Dst Port	2000
DNS Header	ID	0x1000
	QR	1
	OPCODE	0
	AA	1
	TC	0
	RD	1
	RA	ANY
	Z	0
	RCODE	0
	QDCOUNT	1
	ANCOUNT	1
	NSCOUNT	1
	ARCOUNT	2
DNS Question section	QNAME	example.com
	QTYPE	MX (0x000F)
	QCLASS	IN (0x0001)
DNS Answer section	NAME	example.com (Pointer 0xC00C)
	TYPE	MX (0x000F)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	10
	PREFERENCE	10
	EXCHANGE	MAIL1.example.com (MAIL1 + Pointer 0xC00C)
DNS Authority section	NAME	example.com (Pointer 0xC00C)
	TYPE	NS (0x0002)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	6
	NSDNAME	NS1.example.com (NS1 + Pointer 0xC00C)
DNS Additional section	NAME	MAIL1.example.com (Pointer 0xC02B)
	TYPE	A (0x0001)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	4
	ADDRESS	192.168.1.11
DNS Additional section	NAME	NS1.example.com (Pointer 0xC03F)
	TYPE	A (0x0001)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	4
	ADDRESS	192.168.0.10

3rd packet.

Standard query from DNS Client1 (TN) to Server1 (NUT)
IP Header	Source Address	CL1_NETZ
IP Header	Destination Address	NUT_NETZ
UDP Header	Src Port	2001
UDP Header	Dst Port	53
DNS Header	ID	0x1001
	QR	0
	OPCODE	0
	AA	0
	TC	0
	RD	1
	RA	0
	Z	0
	RCODE	0
	QDCOUNT	1
	ANCOUNT	0
	NSCOUNT	0
	ARCOUNT	0
DNS Question section	QNAME	example.com
	QTYPE	MX (0x000F)
	QCLASS	IN (0x0001)

4th packet.

Any order of DNS Answer section 1 and 2 is acceptable.

Any order of DNS Additional section 1, 2 and 3 is acceptable.

If DNS Answer section order is opposite, DNS Additional section 1's NAME pointer is 0xC041, and 2's NAME pointer is 0xC02B.

Standard query response from DNS Server1 (NUT) to Client1 (TN)
IP Header	Source Address	NUT_NETZ
IP Header	Destination Address	CL1_NETZ
UDP Header	Src Port	53
UDP Header	Dst Port	2001
DNS Header	ID	0x1001
	QR	1
	OPCODE	0
	AA	ANY
	TC	0
	RD	1
	RA	ANY
	Z	0
	RCODE	0
	QDCOUNT	1
	ANCOUNT	2
	NSCOUNT	1
	ARCOUNT	3
DNS Question section	QNAME	example.com
	QTYPE	MX (0x000F)
	QCLASS	IN (0x0001)
DNS Answer section 1	NAME	example.com (Pointer 0xC00C)
	TYPE	MX (0x0001)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	10
	PREFERENCE	10
	EXCHANGE	MAIL1.example.com (MAIL1 + Pointer 0xC00C)
DNS Answer section 2	NAME	example.com (Pointer 0xC00C)
	TYPE	MX (0x000F)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	10
	PREFERENCE	20
	EXCHANGE	MAIL2.example.com (MAIL1 + Pointer 0xC00C)
DNS Authority section	NAME	example.com (Pointer 0xC00E)
	TYPE	NS (0x0002)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	6
	NSDNAME	NS1.example.com (NS1 + Pointer 0xC00C)
Additional section 1	NAME	MAIL1.example.com (Pointer 0xC02B)
	TYPE	A (0x0001)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	4
	ADDRESS	192.168.1.11
Additional section 2	NAME	MAIL2.example.com (Pointer 0xC041)
	TYPE	A (0x0001)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	4
	ADDRESS	192.168.1.12
DNS Additional section	NAME	NS1.example.com (Pointer 0xC055)
	TYPE	A (0x0001)
	CLASS	IN (0x0001)
	TTL	1 day (86400)
	RDLENGTH	4
	ADDRESS	192.168.0.10

Exp.

NUT_NETZ	DNS Server1's (NUT) Net-z address
CL1_NETZ	DNS Client1's (TN) Net-z address

JUDGMENT

        2. Received standard query response including MX type record.
        4. Received standard query response including multiple MX type records.

TERMINATION

        None

REFERENCE

        RFC1034 DOMAIN NAMES - CONCEPTS AND FACILITIES
        3.6 Resource Records

        RFC1035 DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION
        3.2.1 Format 
        3.2.2 TYPE values 
        3.3.9 MX RDATA format