Meaning of different command prompts

Unix/Linux: $: can be run as normal user
Unix/Linux: #: must be run as root (or with sudo)
Windows: >: Command Prompt or PowerShell
Windows: PS>: PowerShell only
Unix/Linux and Windows: $/>,#/>: Works in Windows and Unix/Linux.

To set up the DHCP service on CentOS, do the following:

0. Install dhcp: # yum install dhcp.

1. Edit the dhcp config file (/etc/dhcp/dhcpd.conf). Add the following, filling in the blanks. Anything in [square brackets] is optional:

subnet ___.___.___.___ netmask ___.___.___.___ {
    option routers ___.___.___.___;
    option subnet-mask ___.___.___.___;
    [option domain-name "________.___";]
    option domain-name-servers ___.___.___.___[, ___.___.___.___];
    range ___.___.___.___ ___.___.___.___;
}

Example: if you had a network 192.0.2.0/24, with a router at 192.0.2.1, and the domain for.example, and you wanted to reserve addresses 192.0.2.1 through 192.0.2.127 for static IP addresses, and you had a DNS server at 192.0.2.2, you'd want the following configuration:

subnet 192.0.2.0 netmask 255.255.255.0 {
    option routers 192.0.2.1;
    option subnet-mask 255.255.255.0;
    option domain-name "for.example";
    option domain-name-servers 192.0.2.0/24;
    range 192.0.2.128 192.0.2.254;
}

2. Start the service by running the command systemctl start dhcpd, and set it to start at boot with systemctl enable dhcpd.

3. Allow the DHCP service through the firewall with the command firewall-cmd --add-service=dhcp --permanent, then reload the firewall with firewall-cmd --reload.