Installing Apache (httpd) version 2.x on Red Hat based systems (Inc CentOS)

Install apache web server (httpd)
yum install httpd

Start apache (httpd) daemon
/etc/init.d/httpd start

Set httpd to start at init levels 3, 4, 5 (This way it will start at the next system restart automatically)
/usr/sbin/chkconfig --level 345 httpd on

Note down the Servers IP Address (e.g. “inet addr:123.123.123.123”)
/sbin/ifconfig

Open a web browser and check you can get a default test page from the webserver.
Open Firefox or IE and browse to http://123.123.123.123

Default location of httpd logs to troubleshoot problems:
cd /var/log/httpd tail error_log tail access_log

Default location of configuration files
cd /etc/htttpd/conf/ vim httpd.conf

Set the ServerName in httpd.conf
Set the ServerName to the server’s hostname (e.g. srv-web-001) to resolve the following warning on startup.
“Could not determine the server's fully qualified domain name, using 127.0.0.1 for ServerName”

Test your new config before restarting httpd
/usr/sbin/apachectl –t

Restart httpd
/etc/init.g/httpd restart
Note: This will kill off all the current httpd processes before it starts a new parent process.
OR
/etc/init.d/httpd graceful
Note: This will kill the parent process and then starts a new one with your new config. This way it leaves the child processes to complete and then when a new child process is required it starts from the new parent process hence using the new configuration file. Using this method saves disrupting connected users.

This is a very basic setup of apache that will currently only serve up one site from your default document root “/var/www/”.
Place your html files into “/var/www/html/”

For example create a file named index.html and insert the following to test your setup further.