On Thu, Mar 17, 2022, 11:57 PM David Wright <deb...@lionunicorn.co.uk> wrote:
> On Thu 17 Mar 2022 at 12:12:28 (+0000), Thomas Pircher wrote > > > > Cool. If you just type resolvectl, it will show you which information it > > got on each interface. > > This is machine F, where /etc/resolv.conf is a file, containing > 192.168.1.1 : > > $ resolvectl > Global > Protocols: +LLMNR +mDNS -DNSOverTLS DNSSEC=no/unsupported > resolv.conf mode: foreign > Current DNS Server: 192.168.1.1 > DNS Servers: 192.168.1.1 > > Link 2 (enp2s2) > Current Scopes: none > Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS > DNSSEC=no/unsupported > > Link 5 (wlp2s4) > Current Scopes: LLMNR/IPv4 LLMNR/IPv6 > Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS > DNSSEC=no/unsupported > $ host www.google.com > www.google.com has address 142.250.138.105 > www.google.com has address 142.250.138.103 > www.google.com has address 142.250.138.106 > www.google.com has address 142.250.138.99 > www.google.com has address 142.250.138.104 > www.google.com has address 142.250.138.147 > www.google.com has IPv6 address 2607:f8b0:4000:80e::2004 > $ host www.lionunicorn.co.uk > www.lionunicorn.co.uk has address 149.255.60.149 > $ > > Those responses were instantaneous. (I don't think I should expect > resolvectl query to work here.) > > And this is machine R, with systemd-resolved running: > > $ ls -l /etc/resolv.conf > lrwxrwxrwx [ … ] /etc/resolv.conf -> > ../run/systemd/resolve/stub-resolv.conf > $ resolvectl > Global > Protocols: +LLMNR +mDNS -DNSOverTLS DNSSEC=no/unsupported > resolv.conf mode: stub > > Link 2 (enp1s0) > Current Scopes: none > Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS > DNSSEC=no/unsupported > > Link 4 (wlan0) > Current Scopes: DNS LLMNR/IPv4 > Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS > DNSSEC=no/unsupported > Current DNS Server: 192.168.1.1 > DNS Servers: 192.168.1.1 > $ host www.google.com > www.google.com has address 142.251.32.196 > www.google.com has IPv6 address 2607:f8b0:4023:1002::63 > www.google.com has IPv6 address 2607:f8b0:4023:1002::67 > www.google.com has IPv6 address 2607:f8b0:4023:1002::93 > www.google.com has IPv6 address 2607:f8b0:4023:1002::69 > ;; connection timed out; no servers could be reached > > $ resolvectl query www.google.com > www.google.com: 2607:f8b0:4000:805::2004 -- link: wlan0 > 142.251.46.132 -- link: wlan0 > Your machine F seems to resolve almost entirely IPv4 addresses for that host. But your machine R resolves almost exclusively IPv6 addresses for it. Could there be an identical hostname assigned to both IPv4 and IPv6 interfaces? In general you want DNS queries to resolve with less than 500msec network latency. Above 1500 to 1700 msec the applications start breaking and network timeouts are hit. Trimming the rest of your email... -- Information acquired via protocol DNS in 33.6ms. > -- Data is authenticated: no > ......... > > Cheers, > David. >
