Information
These requirements are set to mitigate the effects of several types of denial of service attacks. Although there is some latitude concerning the settings themselves, the requirements attempt to provide reasonable limits for the protection of the web server. If necessary, these limits can be adjusted to accommodate the operational requirement of a given system.
From Apache.org: The StartServers directive sets the number of child server processes created on startup. As the number of processes is dynamically controlled depending on the load, there is usually little reason to adjust this parameter.
The default value differs from MPM to MPM. For worker the default is StartServers 3. For prefork defaults to 5 and for mpmt_os2 to 2.
Solution
Open the httpd.conf file with an editor and search for the following directive:
StartServer
Set the directive to a value between 5 and 10, add the directive if it does not exist.
It is recommended that the directive be explicitly set to prevent unexpected results if the defaults change with updated software.