First a little background. I'm using a Fedora 33 system in a qemu VM. I was doing some research on a question which arose on a Fedora mailing list regarding changes to FallbackDNS. I don't know if this change was universal or Fedora only. But a recent update changed the default to have no FallbackDNS servers defined.
In doing my research I used the default install of Fedora 33 which is running systemd-246.6-3.fc33. I did not supply a DNS server in the static IP settings and I purposely created a broken /etc/systemd/resolved.conf file with the bad entry of DNS=192.168.1.142,192.168.1.1 DNS resolution works and I fully expected that one of the defined FallbackDNS servers would be used. However, resolvectl shows Global LLMNR setting: resolve MulticastDNS setting: no DNSOverTLS setting: no DNSSEC setting: no DNSSEC supported: no Fallback DNS Servers: 1.1.1.1 8.8.8.8 1.0.0.1 8.8.4.4 2606:4700:4700::1111 2001:4860:4860::8888 2606:4700:4700::1001 2001:4860:4860::8844 DNS Domain: greshko.com Link 2 (enp1s0) Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6 DefaultRoute setting: yes LLMNR setting: yes MulticastDNS setting: no DNSOverTLS setting: no DNSSEC setting: no DNSSEC supported: no Current DNS Server: fe80::5054:ff:fe9a:e849%32767 DNS Servers: fe80::5054:ff:fe9a:e849%22096 DNS Domain: ~. The IPv6 address of fe80::5054:ff:fe9a:e849 is that of the Virtual Bridge and wireshark does confirm DNS requests are being sent to that address' port 53 where dnsmasq is running. I have no idea how systemd-resolved discovered this server? Why wasn't a Fallback Server selected used? Then, continuing my research I upgraded systemd to systemd-246.10-1.fc33. In that version there are no FallbackDNS servers defined by default. Owing to previous behavior I was expecting DNS resolution to still work. (Not that I really wanted it to) But it didn't. [egreshko@f33T ~]$ host cnn.com Host cnn.com not found: 2(SERVFAIL) and [egreshko@f33T ~]$ resolvectl Global Protocols: LLMNR=resolve -mDNS -DNSOverTLS DNSSEC=no/unsupported resolv.conf mode: stub DNS Domain: greshko.com 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? _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
