How to determine the last message in sequence in DNS TCP responce
I make DNS zone transfer request (aka AXFR) via TCP to the server. The answer is too big (>100Kb), so it could not be sent in one TCP message. So the server send me a sequence of messages. How can I determine which message is the last? I can't found anything about it's count in the first message. I can't found any special flag in the last one. I can't found anything about it in RFC1035. Could you please explain how to find "end of answer"?
On 27/02/2019 17:21, Владимир Мартьянов wrote: Hi Vladimir,
I make DNS zone transfer request (aka AXFR) via TCP to the server. The answer is too big (>100Kb), so it could not be sent in one TCP message. So the server send me a sequence of messages.
How can I determine which message is the last? I can't found anything about it's count in the first message. I can't found any special flag in the last one. I can't found anything about it in RFC1035.
Could you please explain how to find "end of answer"?
A zone transfer starts with the SOA record of the zone, and ends with the same SOA record. That's how you know that the transfer is complete. To learn more about zone transfers, see RFC 5936, section 2.2: https://tools.ietf.org/html/rfc5936 Regards, Anand Buddhdev RIPE NCC
On Wed, Feb 27, 2019 at 07:21:26PM +0300, Владимир Мартьянов wrote:
I make DNS zone transfer request (aka AXFR) via TCP to the server. The answer is too big (>100Kb), so it could not be sent in one TCP message. So the server send me a sequence of messages.
How can I determine which message is the last? I can't found anything about it's count in the first message. I can't found any special flag in the last one. I can't found anything about it in RFC1035.
Could you please explain how to find "end of answer"?
It has a trailing SOA RR. See RFC 5936 section 2.2. Mukund
participants (3)
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Anand Buddhdev -
Mukund Sivaraman -
Владимир Мартьянов