DHCP

supersede setting value;

request setting;
require setting;

supersede domain-name "example.com";
supersede domain-name-servers 192.168.1.2;
supersede nis-domain "";
supersede nis-servers "";
supersede ntp-servers "ntp.example.com ";
supersede routers 192.168.1.1;
supersede time-offset -18000;
request subnet-mask;
require subnet-mask;

option domain-name
option domain-name-servers
option nis-domain
option nis-servers
option ntp-servers
option routers
option time-offset

$ apt-get remove isc-dhcp-server