In recent versions of CentOS, there are new command line tools to
perform old sysadmin tasks. Do you want to change the hostname of a
machine? Rather than using the hostname command, the hostnamectl
command is the new preferred way to do this.
Do you want to assign a machine a static IP? The semi-old way was to
disable NetworkManager so that you could set the static IP the classic
way via /etc/sysconfig/network-scripts/..., but nowadays you can
also configure static IPs via NetworkManager, thus obviating the need
to disable NetworkManager to perform this configuration. Use nmcli
to perform command-line configuration of NetworkManager.
20190725/DuckDuckGo hostnamectl
20190725/https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/networking_guide/sec_configuring_host_names_using_hostnamectl
20190725/DuckDuckGo nmcli set domain name
20190725/DuckDuckGo nmcli connection modify search domain
20190725/https://unix.stackexchange.com/questions/336727/centos7-network-manager-is-using-wrong-search-domain#336730
20190802/DuckDuckGo networkmanager assign static ip
20190802/https://askubuntu.com/questions/246077/how-to-setup-a-static-ip-for-network-manager-in-virtual-box-on-ubuntu-server