Re: [Acme] Support for domains with redundant but not immediately synchronized servers

Michael Wyraz <michael@wyraz.de> Tue, 09 February 2016 11:11 UTC

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From: Michael Wyraz <michael@wyraz.de>
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Date: Tue, 9 Feb 2016 12:11:48 +0100
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Subject: Re: [Acme] Support for domains with redundant but not immediately synchronized servers
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Hello Jonas,

thank you for the proposal. I think addressing such setups is a good idea.

The solution you propose works only if dns round robin is used (i.e. all
the real server ips in A or AAAA). But there are similar setups where
the redundant servers are behind some load balancer where a completely
different ip is used. Another widely used scenario is geo-based dns. In
this case, the Acme server would only see his "nearest" ip address.

IMO a better way to support your scenario as well as those I described
above would be to check for an SRV-Record before checking A-Records.
This would be 100% compatible with existing acme http-01 clients. In
your case you would resolve the SRV record to the machine that has the
acme client running on. The acme-server would check for the SRV-Record
for an address to lookup the challenge's response at. If no SRV record
is specified, it would continue with A and AAAA records.

Kind regards,
Michael.

>
>
> On 21.01.2016 15:13, Salz, Rich wrote:
>
> >> I am not at all familiar with the processes in an IETF WG. What
> >> is the way forward to get my proposal either into the protocol or
> >> officially dismissed?
>
> > This is the way it works. :)  People post to the mailing list and
> > there's discussion.  At some point, the chairs will see if there is
> > consensus to do it.
>
> > So things are working as designed.  It's informal and a bit messy.
>
> > What might help focus discussion is if you made a pull request with
> > your specific wording changes.
>
> I gave it a shot: https://github.com/ietf-wg-acme/acme/pull/82
>
> I will appreciate any feedback on that proposal.
>
> best regards,
> jwi
> > _______________________________________________ > Acme mailing list >
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