service httpd restart

check the status of Apache
[vagrant@localhost ~]$ /etc/init.d/httpd status
httpd status unknown due to insufficient privileges.

restart apache
[vagrant@localhost ~]$ sudo service httpd restart
httpd を停止中: [ OK ]
httpd を起動中: httpd: Could not reliably determine the server’s fully qualified domain name, using localhost.localdomain for ServerName
[ OK ]