The servers don’t return NXDOMAIN for non existent names. -- Mark Andrews
> On 28 Mar 2023, at 22:01, Peter DeVries <[email protected]> wrote: > > <snip> > >> The queries for "_.extglb.tn.gov. IN A ?" in your PCAP are a novelty to >> me. Are these some form of query minimisation, or some sort of sanity >> check of the delegation? Sadly, the "tn.gov" nameserver just drops >> these without responding, so their failure could well contribute to the >> problems you observe. > > These are indeed how BIND does qname minimization in "relaxed" mode > which is currently the default. > > We almost blocked these because we didn't know what they were but then > I stumbled upon one of the old RFC drafts for query minimization and > it does mention this as a technique. I could see someone else doing > so as well because it did make up a very large percentage of our > inbound queries and there isn't much documentation on it. > > Peter _______________________________________________ dns-operations mailing list [email protected] https://lists.dns-oarc.net/mailman/listinfo/dns-operations
