I recently updated my Ubuntu which ended in a shot DNS config.
I am able to add a nameserver to /etc/resolvconf/resolv.conf.d/tail (and restart the service) to get DNS resolution for everything internet related.
Doing this also means i will never be able to resolve local IPs and names (and vice versa). This can be very helpful especially in big intranets like the internal network of a university. Although i have no idea how and why, this worked prior to the update.
I was under the impression, that usually a DNS request is sent to the default gateway for the respective interface, if no other DNS server is specified.
Is this correct?
Whithout any other DNS server specified, the only nameserver in /etc/resolv.conf is 127.0.0.53, the "systemd-resolv stub resolver".
Is there any way to configure systemd-resolv or resolvconf to send a DNS request to the default gateway of the interface specified by the routing table?
(When i use dig @(default gateway) (name of local machine/domain name) i get a correct response. This means my home access point/router is able to answer DNS requests)
/etc/network/interfaces
then use thedns-nameservers
option