Apache proxy for CentOS 5 network installation

CentOS 5 provides a network installation image but during the network installation it is not possible to configure a proxy. The following configuration emulates a CentOS mirror with an Apache proxy.

<IfModule mod_proxy.c>
  ProxyPass /centos http://mirror.centos.org/centos
  ProxyPassReverse /centos http://mirror.centos.org/centos
  ProxyRemote * http://proxy:3128
</IfModule>

It is necessary to enable the Apache modules proxy and proxy_http. After that it is possible to start the installation with the IP address of the Apache proxy and the URL /centos/5/os/i386.