Subject: Re: Sense of the WG: mDNS configuration?

From: Stuart Cheshire <[email-masked]>
Date: Sat, 15 Sep 2001 14:45:15 -0700

Just when I think we've all agreed that it's a bad idea to overload the 
DNS search list to configure mDNS, someone always seems to suggest it 
again.

In case there is anyone still in favour of that alternative, let me make 
the following comment:

>Currently the DNS server addresses and the domain searchlist can be
>statelessly discovered in IPv6, but the other candidates cannot be,
>thereby creating a DHCPv6 dependency, which is a show-stopper.

I really believe this is misleading reasoning.

Yes, it is true that discovering the domain search list statelessly in 
IPv6 avoids the need for a DHCP server, but if we overload the DNS search 
list to control this aspect of host configuration, where do we stop? Do 
we configure the default printer by adding an entry to the search list 
with the name "your.default.printer.is.printer1.ietf.org."? I could 
easily define an encoding to let you embed *any* legal DHCP option as an 
entry in the search list.

Maybe it would be a good idea to just get rid of DHCPv6 and use some 
DNS-based solution to retrieve host configuration information, but that 
would be a much larger discussion, not some ad-hoc hack just for this 
specific purpose.

Stuart Cheshire <[email-masked]>
 * Wizard Without Portfolio, Apple Computer
 * Chairman, IETF ZEROCONF
 * www.stuartcheshire.org

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From: Bernard Aboba <[email-masked]>
Date: Sun, 16 Sep 2001 00:26:59 -0700 (PDT)

> DNS search list to configure mDNS, someone always seems to suggest it 

Actually, we haven't heard all that many arguments in favor of the domain
searchlist as of late. So you may be preaching to the choir ;)

> list to control this aspect of host configuration, where do we stop? 

Actually, I don't believe that is the approach that DNS Discovery is
taking, although there *is* a proposal for a general method of encoding
parameters in a (new? TXT?) DNS RR. 

> would be a much larger discussion, not some ad-hoc hack just for this 

I'll let someone else comment on whether the proposals are an "ad-hoc
hack", but the DNS Discovery work is not motivated by the desire to
configure mDNS. Rather the goal is to configure statelessly configure DNS.