how to change dns server manually linux code example
Example: change dns linux
sudo vim /etc/resolvconf/resolv.conf.d/base
# add nameserver(s) like this.
nameserver 8.8.8.8
nameserver 8.8.4.4
$ sudo resolvconf -u
sudo vim /etc/resolvconf/resolv.conf.d/base
# add nameserver(s) like this.
nameserver 8.8.8.8
nameserver 8.8.4.4
$ sudo resolvconf -u