The name of the machine. Leave it empty if you want to obtain it from a DHCP server (if using DHCP). The hostname must be a valid DNS label (see RFC 1035 section 2.3.1: "Preferred name syntax", RFC 1123 section 2.1: "Host Names and Numbers") and as such must not contain the domain part. This means that the hostname must start with a letter or digit, end with a letter or digit, and have as interior characters only letters, digits, and hyphen. The maximum length is 63 characters. Additionally it is recommended to only use lower-case characters. If (e.g. for legacy reasons) a FQDN is required as the Linux kernel network node hostname (uname --nodename) the option boot.kernel.sysctl."kernel.hostname" can be used as a workaround (but the 64 character limit still applies).
WARNING: Do not use underscores (_) or you may run into unexpected issues.
string matching the pattern ^$|^[[:alnum:]]([[:alnum:]_-]{0,61}[[:alnum:]])?$config.system.nixos.distroId