If you just want to flood the traffic then using of metasploit is more effective then hping. To perform DoS attack using kali with metasploit you first need to start Metasploit, if you don’t know how to start metasploit I suggest you to go through my article How to start Metasploit in Kali 2 ?
Once you have started msf you will get console like below:-
now select proper auxiliary module with use command:-
msf > use auxiliary/dos/tcp/synflood
now metasploit is ready to use synflood module, Check all available options for this module
as you can see it says RHOST, RPORT, TIMEOUT, SNAPLEN are required field and other are not compulsory to launch this attack. SNAPLEN, TIMEOUT and RPORT are preconfigured you can change them if you want, for this article I will not change as we are going to launch attack on http website only. So we need to set RHOST:-
set RHOST 192.168.100.1
now that all the required fields are set we can launch DoS Attack using Kali with run command:
You can set attack speed depending upon your own internet speed and TIMEOUT value you have configured.