Why is fully qualified domain name of local machine in the /etc/host file given an IP address of 127.0.1.1 and not 127.0.0.1 since it is a local host?

Question

I have an Orange Pi Zero board flashed with Armbian Linux and Ubuntu 24.04 Server. The content of its /etc/hosts file is:

root@orangepizero:~# cat /etc/hosts
127.0.0.1   localhost
127.0.1.1   orangepizero
::1         localhost orangepizero ip6-localhost ip6-loopback
fe00::0     ip6-localnet
ff00::0     ip6-mcastprefix
ff02::1     ip6-allnodes
ff02::2     ip6-allrouters

Question:

Why is the fully qualified domain name (FQDN) orangepizero in /etc/hosts given an IP address 127.0.1.1 and not 127.0.0.1? I ask this because orangepizero is the localhost. Also, the IP address ::1 is also given the fully qualified domain names localhost and orangepizero.

This situation seems occur in other Linux systems that I have come across. The FQDN of the local machine is often give the IP address of 127.0.1.1 and not 127.0.0.1. Why is this so?

Why is fully qualified domain name of local machine in the /etc/host file given an IP address of 127.0.1.1 and not 127.0.0.1 since it is a local host?

0 Answers0