DHCP server Info

Dhcpd (also spelled DHCPD or referred to as DHCP) is the daemon that allows a Linux computer to act as a DHCP server.

DHCPD is used to by the dhcp to give users an IP address. The way this works is when a user asks for a IP the dhcp looks at the dhcpd.conf, so that is can see what IP it can offer from the IP range table. These IPs are only giving for a certain amount of time which is set in the dhcpd.conf file this is called lease time. When the assigned IP has expired the user is asked to renew its IP and then is given a new IP.

The way the dhcpd tracks what IPs it has given out already is through listing all of the IP's in the dhcpd.leases file. The reason for this is because if there were to be a power loss the dhcpd.leases file will not be erased and will not forget the IPs given out already. When the DHCP file is being accessed it refers to the leases file to see what IPs the dhcpd has given out.

Here are some of the commands for DHCPD. -p is to listing on another port, because by default it will listen on port 67. -f this will make dhcpd run on the foreground not in the background as a demond. -d is to debug the conf file. -T is to test the dhcpd.conf file in the simplest way.