Re: [DNSOP] draft-ietf-dnsop-glue-is-not-optional-07 vs. sibling glue

[Peter Thomassen <[e-mail]>]

On 3/28/23 03:14, Shumon Huque wrote:
> On Tue, Mar 28, 2023 at 3:45 AM Viktor Dukhovni <[e-mail] <mailto:[e-mail]>> wrote:
> 
>     On Wed, Mar 01, 2023 at 04:27:31PM -0500, Shumon Huque wrote:
>     Can we at least state that domains with cyclic dependencies are a bad
>     idea, and may not be supported by all resolvers.  In other words, that
>     the domain owner can't **rely** on the sibling glue recommended to be
>     sent in this draft to save the day.
> 
>     My strong preference is still to delete all reference in the draft to
>     cyclic dependencies (i.e. not enshrine bad practice).  Which leaves
>     sibling glue primarily as a performance optimisation, and secondarily
>     as a last resort when the nameserver IP addresses are wrong or gone
>     from the authoritative zone (another bad practice).
> 
> 
> Viktor - I've so far not seen many other people speak up in support of your
> position. I suspect this is because this draft was discussed to death many
> months ago during long discussion threads on the list, and there is likely
> already rough consensus for the current content. Personally, I would be ok
> with adding a statement that configurations involving cyclic dependencies
> are not recommended, but others will likely have to also speak up in support
> of this too.

I support adding such a statement about cyclic dependencies.

In addition, I would support saying that data suggests that, while (non-cyclic) glue records may have a benefit in certain cases, they frequently are a source of harm (time-outs), and the trade-off remains unclear.

FWIW, I hold this opinion because I find Viktor's numbers pretty convincing. However, as I've never operated a resolver, I'm convinced solely based on what I've read (to the best of my ability), not based on what I've experienced. Others' first-hand experience may be more material.

~Peter