Either the config on the device is wrong, there is supposed to be a dns ON the device or the dhcp server is handing out wrong dns to the device. Not on every specific device if there is a local dns server available on the network. Then it's normally done on the local dns itself by first checking local configs (like /etc/hosts) and if not available, resolve it using online dns servers. And the dhcp server is obv configured to point to the local dns server. That way the configs gets propagated via the dhcp lease to all devices on the network. Edit As far as I know, network manager is default on armbian (correct me if I'm wrong) and that should have edited your /etc/resolv.conf. So since it's not, you have made changes outside of default config somehow.

gene@amanda:~$ resolvectl status Global Protocols: -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported resolv.conf mode: stub Link 2 (end0) Current Scopes: DNS Protocols: +DefaultRoute -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported Current DNS Server: 192.168.71.0 DNS Servers: 192.168.71.0

untouched and wrong as can be: # # This file might be symlinked as /etc/resolv.conf. If you're looking at # /etc/resolv.conf and seeing this text, you have followed the symlink. # # This is a dynamic resolv.conf file for connecting local clients to the # internal DNS stub resolver of systemd-resolved. This file lists all # configured search domains. # # Run "resolvectl status" to see details about the uplink DNS servers # currently in use. # # Third party programs should typically not access this file directly, but only # through the symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a # different way, replace this symlink by a static file or a different symlink. # # See man:systemd-resolved.service(8) for details about the supported modes of # operation for /etc/resolv.conf. nameserver 127.0.0.53 options edns0 trust-ad search . Damn, doesn't anyone use /etc/hosts for small home networks anymore? Toss in that you don't install ANY manpages so us users are running blind 99% of the time. Thanks bedna.

I repeat, what is in your /etc/resolv.conf?

the router reflashed with a recent dd-wrt runs dnsmasq, which caches the ISP. If that fails it query's the ISP's server, which works fine for the other 7 machines here.