There is a defect-attractor in DNS-packet construction. When people writes `.`-ending in a DNS name in config (eg in order to avoid search-suffix behaviour), some software will construct an invalid DNS question:

There is a defect-attractor in DNS-packet construction. When people writes `.`-ending in a DNS name in config (eg in order to avoid search-suffix behaviour), some software will construct an invalid DNS query:

For more background, https://jvns.ca/blog/2022/09/12/why-do-domain-names-end-with-a-dot-/

For more background, https://jvns.ca/blog/2022/09/12/why-do-domain-names-end-with-a-dot-/#in-a-dns-request-response-domain-names-don-t-have-a-trailing or view responses in various formats https://dnsinstitute.com/webdnsquery/