systemd Developer Lennart Poettering lennart@poettering.net hostname 5 hostname Local host name configuration file /etc/hostname The /etc/hostname file configures the name of the local system that is set during boot, with the sethostname2 system call. It should contain a single newline-terminated host name string. The host name may be a free-form string up to 64 characters in length, however it is recommended that it consists only of 7bit ASCII lower-case characters and no spaces or dots, and limits itself to the format allowed for DNS domain name labels, even though this is not a strict requirement. Depending on the operating system other configuration files might be checked for configuration of the host name as well, however only as fallback. You may use hostnamectl1 to change the value of this file from the command line. The simple configuration file format of /etc/hostname originates from Debian GNU/Linux. systemd1, sethostname2, hostname1, hostname7, machine-id5, machine-info5, hostnamectl1, systemd-hostnamed.service8