* Tony Finch: > bert hubert <[email protected]> wrote: >> >> It is all optional, and nobody does anything with that data. In fact stub >> resolvers do very little with what they receive. So for example, even the >> additional processing for an MX record is completely ignored mostly. > > Yes. > > The difficulty with MX (and SRV) additional data is that you don't get a > clear indication whether the target address records are nonexistent or > just unavailable, so it tends to be easier to look them up regardless of > the contents of the additional section.
Exactly. Exim tried to do the optimization, but did not cover a corner case, and we had very obscure intermittent mail delivery failures as a result. Not nice. _______________________________________________ dns-operations mailing list [email protected] https://lists.dns-oarc.net/mailman/listinfo/dns-operations dns-jobs mailing list https://lists.dns-oarc.net/mailman/listinfo/dns-jobs
