remove apache2 from ubuntu
#stop the apache2 service
$ sudo systemctl stop apache2
#remove apache2 packages
$ sudo apt-get purge apache2 apache2-utils apache2-bin apache2.2-common
# cleanup
$ sudo apt-get autoremove
# check if the apache has been removed:
#1- following command line should return a blank line
$ which apache2
# 2- following command line should return apache2: Failed to start apache2.service: Unit apache2.service not found.
$ sudo systemctl start apache2