hosts(5) File Formats Manual hosts(5) hosts - /etc/hosts /etc/hosts. IP IP. : _IP __ [_...] IP IPv4 IPv6. / . "#" . ("-") ("."). . ( localhost). (IPv4 IPv6). (BIND) UNIX. /etc/hosts /etc/hosts . DNS : . DNS . NIS NIS NIS. NIS DNS NIS . DNS. DNS . /etc/hosts . RFC 952 . DNS . (NIC) / . NIC hosts.txt ( 2000) hosts.txt . 92 94 95. # The following lines are desirable for IPv4 capable hosts 127.0.0.1 localhost # 127.0.1.1 is often used for the FQDN of the machine 127.0.1.1 thishost.example.org thishost 192.168.1.10 foo.example.org foo 192.168.1.13 bar.example.org bar 146.82.138.7 master.debian.org master 209.237.226.90 www.opensource.org # The following lines are desirable for IPv6 capable hosts ::1 localhost ip6-localhost ip6-loopback ff02::1 ip6-allnodes ff02::2 ip6-allrouters hostname(1), resolver(3), host.conf(5), resolv.conf(5), resolver(5), hostname(7), named(8) RFC 952 3 . . : . 6.18 11 2026 hosts(5)