Kill all instances of httpd

If a process is hanging in a bad state and it won’t go away even after sending it a SIGTERM, you can send it the SIGKILL (Signal number 9) signal, which is a forced shutdown of a process. Note that with SIGKILL the process will not have opportunity to clean up any system resources it was using (e.g. temporary files etc.). For example:

# kill -9 6041

(Will forcefully kill process with PID 6041)

Generally system administrators will find the PID of the process to which they want to send the signal by using the ps command, and then use the kill command to send a signal to that PID. But it is also possible to send a signal to process by its name. For example:

# killall httpd

(will send SIGTERM to all httpd processes)