<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> </head> <body> <div class="moz-cite-prefix">On 20/02/2021 00:30, Lennart Poettering wrote: </div> <blockquote type="cite" cite="mid:YC%2FnqEGMmpZH%2Fx59@gardel-login"> <pre class="moz-quote-pre" wrap="">The fallback servers are only used as last resort, if there's nothing else known. They are *fallback* as the name says. Most likely the DNS servers were acquire by your network management solution (NetworkManager or networkd) and set on the device. Maybe theym come from IPv6 RA?</pre> </blockquote> OK. I have found that, using wireshark, there is a Type: Router Solicitation (133) followed by Type: Router Advertisement (134) which contains ICMPv6 Option (Recursive DNS Server fe80::5054:ff:fe9a:e849) <blockquote type="cite" cite="mid:YC%2FnqEGMmpZH%2Fx59@gardel-login"> <blockquote type="cite"> <pre class="moz-quote-pre" wrap="">Then, continuing my research I upgraded systemd to systemd-246.10-1.fc33. In that version there are no FallbackDNS servers defined by default. </pre> </blockquote> <pre class="moz-quote-pre" wrap=""> Yeah, i think that's a bad change. I am not sure where the benefit of having a non-working system is...</pre> </blockquote> Scratching my head on that one as well. <blockquote type="cite" cite="mid:YC%2FnqEGMmpZH%2Fx59@gardel-login"> <blockquote type="cite"> <pre class="moz-quote-pre" wrap="">Link 2 (enp1s0) Current Scopes: LLMNR/IPv4 LLMNR/IPv6 Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported So, now my question, why wasn't the dnsmasq server found/configured as had been the case? An intentional change or unintentional change? </pre> </blockquote> <pre class="moz-quote-pre" wrap=""> I am not sure which software manages that interface, but it would be worth figuring that out, and then checking whether it propagated that DNS info to resolved. </pre> </blockquote> Well, I determined that in both the systemd-246.6-3 and systemd-246.10-1 cases (the only changes made) the same Router Solicitation and Router Advertisement occur. So, the only conclusion that I can come to is that something changed between the two versions of systemd which results in the Recursive DNS Server option being ignored. Would you consider this a candidate for a bug report against systemd? </body> </html>