Re: [v6ops] IPv6-Only Preferred DHCPv4 option

Ted Lemon <mellon@fugue.com> Mon, 09 December 2019 14:17 UTC

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From: Ted Lemon <mellon@fugue.com>
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Date: Mon, 09 Dec 2019 06:17:10 -0800
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Cc: Lorenzo Colitti <lorenzo@google.com>, V6 Ops List <v6ops@ietf.org>
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To: "Bernie Volz (volz)" <volz@cisco.com>
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Subject: Re: [v6ops] IPv6-Only Preferred DHCPv4 option
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On Dec 9, 2019, at 06:00, Bernie Volz (volz) <volz@cisco.com> wrote:
> 
> We already don’t commit to disk per rfc2131 and use a short, tuneable time-out. So, again, we are all set without server changes. 

Does rfc2131 actually say that?

> You can also classify these devices into a separate client class to reduce timeout for them (such as to a few seconds).
> 

That’s a special server change. 

> Again, I see no need for special server changes.
> 
> If a server doesn’t provide for these mechanics, the server should. But this is configuration issue, not protocol issue.

So servers other than yours should be the ones that have to change?  :)

The reason I think this merits a change is that we actually want different behavior. The change is trivial.

You aren’t actually arguing for no change: you are arguing for a change that is minimally inconvenient assuming a certain existing implementation.

That is a good short term move, but this is a long term solution. So I’m arguing to do it right. 

One way to resolve this impasse would be to specify it do it would work with your minimal change, but also allow the server to send no address in the offer. That way you can implement the full change at your leisure, but we still get a good long term outcome.