OpenBSD: Reload / Restart / Stop dhcpd Server Command

I manage MS-Windows server and recently started to play with OpenBSD server. How do I reload or restart the dhcpd server on OpenBSD using shell command line option?

Tutorial details
Difficulty level	Easy
Root privileges	Yes
Requirements	dhcpd
Est. reading time	1m

If you made changes to the configuration of your DHCP (dhcpd) server, you will have to stop and restart the server manually. On OpenBSD and Unix like operating system, you kill the dhcpd server and restart manually. Another option is to send HUP (SIGHUP) to dhcpd server.

Method#1: Find dhcpd PID and kill it

Type the following ps command to find dhcpd PID as root user:
# ps ax | grep dhcpd
Sample outputs:

USER       PID %CPU %MEM   VSZ   RSS TT   STAT STARTED       TIME COMMAND
_dhcp    13420  0.0  0.1   588   568 ??  Ss    10:27PM    0:00.04 dhcpd re0

You need to kill that process with kill command.
# kill -9 13420

To start dhcpd, type the following commands:
# touch /var/db/dhcpd.leases
# dhcpd -q re0

Method #2: Say hello to /etc/rc.d/dhcpd script

You can skip all of the above commands. Use rc script as follows to start, stop, restart, and check dhcpd server on OpenBSD:
/etc/rc.d/dhcpd start
/etc/rc.d/dhcpd stop
/etc/rc.d/dhcpd restart
/etc/rc.d/dhcpd check

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