Can a NAPTR query over TCP contain OPT section in Additional Records
Harshith Mulky
harshith.mulky at outlook.com
Thu Jun 22 12:36:12 UTC 2017
Hello Experts,
I am having this Call Flow
Client
DNS
EDNS query, buffer size=4096
------------------------------------------------------->
DNS Response, Truncation bit set (TC=1)
<-------------------------------------------------------
DNS Query over TCP
------------------------------------------------------->
DNS Response over TCP
<------------------------------------------------------
In the above Call Scenario, I have the Client supporting, edns Buffer
Size=4096. and on the server, I have enabled this: to limit the server
sending > 512 bytes in Response
server 0.0.0.0/0 {
edns yes;
edns-udp-size 512; //max size query sever can receive is upto 4096
bytes(default value=4096 )
max-udp-size 512; //max size server can transfer is upto 4096
bytes(default value =4096)
};
The EDNS query is OK, the response is also OK
The question is regarding the DNS Query over TCP,
Can the DNS Query over TCP include the OPT RR section, is this not
Applicable to only UDP? is there any RFC which supports OPT RR section for
query over TCP
Traces:
Transmission Control Protocol, Src Port: 65168 (65168), Dst Port: domain
(53), Seq: 1, Ack: 1, Len: 42
Source port: 65168 (65168)
Destination port: domain (53)
[Stream index: 5]
Sequence number: 1 (relative sequence number)
[Next sequence number: 43 (relative sequence number)]
Acknowledgement number: 1 (relative ack number)
Header length: 32 bytes
Flags: 0x18 (PSH, ACK)
000. .... .... = Reserved: Not set
...0 .... .... = Nonce: Not set
.... 0... .... = Congestion Window Reduced (CWR): Not set
.... .0.. .... = ECN-Echo: Not set
.... ..0. .... = Urgent: Not set
.... ...1 .... = Acknowledgement: Set
.... .... 1... = Push: Set
.... .... .0.. = Reset: Not set
.... .... ..0. = Syn: Not set
.... .... ...0 = Fin: Not set
Window size: 29312 (scaled)
Checksum: 0x479c [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
Options: (12 bytes)
NOP
NOP
Timestamps: TSval 275757710, TSecr 3185381708
[SEQ/ACK analysis]
[Number of bytes in flight: 42]
[PDU Size: 42]
Domain Name System (query)
[Response In: 113]
Length: 40
Transaction ID: 0x62f0
Flags: 0x0100 (Standard query)
0... .... .... .... = Response: Message is a query
.000 0... .... .... = Opcode: Standard query (0)
.... ..0. .... .... = Truncated: Message is not truncated
.... ...1 .... .... = Recursion desired: Do query recursively
.... .... .0.. .... = Z: reserved (0)
.... .... ...0 .... = Non-authenticated data: Unacceptable
Questions: 1
Answer RRs: 0
Authority RRs: 0
Additional RRs: 1
Queries
alabamat1.com: type NAPTR, class IN
Name: alabamat1.com
Type: NAPTR (Naming authority pointer)
Class: IN (0x0001)
Additional records
<Root>: type OPT
Name: <Root>
Type: OPT (EDNS0 option)
UDP payload size: 4096
Higher bits in extended RCODE: 0x0
EDNS0 version: 0
Z: 0x8000
Bit 0 (DO bit): 1 (Accepts DNSSEC security RRs)
Bits 1-15: 0x0 (reserved)
Data length: 0
--
View this message in context: http://bind-users-forum.2342410.n4.nabble.com/Can-a-NAPTR-query-over-TCP-contain-OPT-section-in-Additional-Records-tp4018.html
Sent from the Bind-Users forum mailing list archive at Nabble.com.
More information about the bind-users
mailing list