Capwap Mailing List: Re: Issue 156: Need more details on use of DNS for discovery

[Pasi.Eronen (Pasi.Eronen]

Pat Calhoun wrote:
>
> Pasi's comment was:
> 
>    Section 3.3: there's a single sentence about DNS-based discovery;
>    probably slightly more details would be useful.
> 
> Well... There's not much else we can say, but I am proposing the
> following text In hopes that it will provide more clarity to the
> implementor.
> 
> <new text>
> 3.3.  AC Discovery
> [...]
>       DNS: The DNS name "CAPWAP-AC-Address" MAY be resolvable to one
>       or more AC addresses.  A WTP that wishes to make use of DNS 
>       SHOULD use the format described in [RFC2782].  The recommended 
>       format for a lookup would be _capwap._udp.example.com.
> </new text>

I have some trouble parsing the 'The DNS name "CAPWAP-AC-Address" MAY
be resolvable...' part. It seems to be suggesting doing a DNS query
for DNS name "CAPWAP-AC-Address" -- or in other words, defining a new 
Top-Level Domain. That probably isn't a good idea.

The two latter sentences are also leaving awfully lot of details to
the implementor -- RFC2782 has specific requirements about the
labels etc.  (E.g. RFC 3861 has much more text about using SRV
records for another purpose.)

Best regards,
Pasi