Re: [dnsext] Some thoughts on the updated aliasing draft

"John Levine" <> Sun, 27 March 2011 22:30 UTC

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Date: Sun, 27 Mar 2011 22:31:14 -0000
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From: John Levine <>
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Subject: Re: [dnsext] Some thoughts on the updated aliasing draft
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>these would be, in the parlance used when this topic was first
>introduced, "second class names".  they can't be used as the target
>of MX or NS RRs, and they won't work for services whose servers have
>not been upgraded.

Seems to me we can do some process of elimination here.

What people would like is a magic DNS hack so that you can tell your DNS
server that a bunch of names are equivalent, and all the other software
on the net treats those names just the same.  Sorry, no pony.  You can't
have that.

If it's an absolute requirement that no software outside the DNS can
change, then our answer is clear: manual name bundling, with manual
configuration of applications, we're done, so long.  I don't hear much
support for that.

So what can we offer?  If it's something like CLONE or BNAME, we offer
an upgrade path.  You're no worse off than you'd be with manual
bundling and manual application configuration, and to the extent you
upgrade your applications to know about the new DNS stuff, your
configuration job gets easier.

That's not as cool as the mythical magic hack.  Will people find it
useful?  Having done my share of SMTP server hackery, I would.  If
it's as important to handle variant names as people say it is, they'll
upgrade.  If not, well, that's OK too.