Linux Local Domain Name Resolution. Nss-mdns is a plugin for the GNU Name Service Switch NSS. The way to change that order is to edit the etcnsswitchconf file with your favourite editor.
The mechanism for name resolution in Linux is modular and can use various sources of information declared in the etcnsswitchconf file. This mechanism uses the etcresolvconf file that well describe later in the chapter. This article explains how to setup a local DNS using the hosts file etchosts in Linux systems for local domain resolution or testing the website before taking live.
DNS works as the phone book for the Internet by translating hostname into IP address or vise versa.
Restart the network service service network restart to set the cache as the local DNS resolver. To do that it uses the the name resolution processes provided by the host machine. By default this service has four different modes for handling the Domain name resolution and uses the systemd DNS stub file runsystemdresolvestub-resolvconf in the default mode of operation. Query remote DNS servers.