Re: [mdnsext] mDNSext features/requirements rollup

[James Andrewartha <[e-mail]>]

On Mon, 28 Jan 2013 12:34:00 -0500, Andrew Sullivan wrote:

> I still do not understand why this sort of thing isn't better handled
> by vastly improved tools for real DNS management.  It seems to me that
> people are asking for a single, unifed namespace outside the
> link-local context, and we invented a mechanism for that many years
> ago.  The problem is that the support tools for that mechanism sort of
> suck.  Instead of inventing a new protocol which, by definition, is
> going to run into conflicts with the existing protocols in this space,
> why wouldn't it be better to take that energy and expend it on the
> missing tools?

I too would like better real DNS management, however there are several
problems with it. Others have pointed out that existing implementations
are focused on mDNS and LL DNS-SD - is WA DNS-SD well tested, has a
useful client UI etc? Imagine having to reconfigure your DNS search
domains when you change location - sure this can be handled by DHCP, but
then you have to have lots of different scopes, which is another
management tool problem.

As for the server side of things, apparently some devices don't support
registration in DNS [1]. A suggestion was made to have a tool that
translates mDNS to updates to a WA DNS-SD domain, which could work, and
does allow administrator approval of what is visible, but there's still
the question of domain scope management. Never mind that some features
of Apple TVs just don't work over WA DNS-SD, only mDNS [2].

Even for applications/devices that do support registration, I don't know
if they support setting a scope for each record. As such, doing it once
at the network level is far easier than updating every DNS-SD publishing
application. For example, I recently discovered [3] that our printers
are published to Mac clients via mDNS from Papercut - how do I control
the visibility of printers in certain areas?

Going back to the broader topic, I also need different scopes for
different folk^Wservices - the area/networks a printer should be
advertised on are different to an Apple TV in a classroom. But a client
iPad needs to see both.

My use case is Apple TVs in each classroom, which I'd like to limit
geographically, both for ease of use (finding an entry is a list of 100
is not fun) and to prevent accidents (streaming to the wrong device).

[1]
http://listserv.educause.edu/cgi-bin/wa.exe?A2=ind1112&L=WIRELESS-LAN&T=0&F=&S=&P=52503
[2]
http://listserv.educause.edu/cgi-bin/wa.exe?A2=WIRELESS-LAN;0pol1g;20111220182540-0600
[3] After installing a new wireless network that appears to be having
trouble with multicast. I've since discovered printers can be pushed out
by profiles, but a) profiles suck compared to MCX, b) profiles have no
location awareness.

[late subscriber to the list, apologies for thread-breaking]

-- 
James Andrewartha
Network & Projects Engineer
Christ Church Grammar School
Claremont, Western Australia
Ph. [phone]
Mob. [phone]