$ nano /etc/hosts
127.0.0.1 localhost
127.0.1.1 user-UBUNTU
# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
127.0.0.1 domain.dev
127.0.0.1 api.domain.dev
127.0.0.1 test.domain.dev