Re: [dnsext] RFC 6604 Clarification

[Jiankang Yao <[e-mail]>]

> 在 2015年3月31日，15:22，"W.C.A. Wijngaards" <[e-mail]> 写道：
> 
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> Hi Kumar,
> 
> I cannot answer on the RFC part, but I want to answer on what will
> make the resolver continue the lookup.
> 
>> On 30/03/15 11:04, Kumar Ashutosh wrote:
>> Hi
>> 
>> As per RFC 6604, section 3
>> 
>> When an xNAME chain is followed, all but the last query cycle
>> 
>> necessarily had no error.  The RCODE in the ultimate DNS response
>> 
>> MUST BE set based on the final query cycle leading to that
>> 
>> response.  If the xNAME chain was terminated by an error, it will
>> 
>> be that error code.  If the xNAME chain terminated without error,
>> 
>> it will be zero.
>> 
>> 
>> 
>> This is a little vague on two accounts:
>> 
>> 1.What would be the error code if the server decides to curtail
>> the CNAME chain after a certain length (say 20). Is it still
>> success or do we indicate in some other way.
> 
> The curtailed CNAME chain is best sent with RCODE NOERROR(0).
> 
>> 




Based on the current text below"
>>   If the xNAME chain terminated without error, it will be zero.
>> "

"Curtail the cname chain" can be regarded as a kind of "terminated without error".
So I agree that it is zero (no error).

Jiankang Yao