When Apache starts, it binds to some port and address on the local machine and waits for incoming requests. By default, it listens to all addresses on the machine. However, it may need to be told to listen on specific ports or only on selected addresses or a combination of both.
eHealth 6.2 uses Apache 2.2.11 web server for hosting the eHealth web user interface and by default it listens to Port 80 unless explicitly specified to listen on any other port
The Listen directive can be used to tell the server to accept incoming requests only on the specified ports or address-and-port combinations. If only a port number is specified in the Listen directive, the server listens to the given port on all interfaces. If an IP address is given as well as a port, the server will listen on the given port and interface. Multiple Listen directives may be used to specify a number of addresses and ports to listen on. The server will respond to requests from any of the listed addresses and ports.
Syntax: Listen [ port | IP-address:port ]
Context: server config
The following steps must be performed as a user with administrator privileges if running a Windows OS and if it?s a Unix machine these steps must be done as the root user.