10.5 Virtual Site Host Features

If only one website can be run on each server running Linux systems, low-traffic grassroots station chiefs will be forced to bear the high cost of server leasing, which will obviously also result in a waste of hardware resources. Before virtual private servers (VPS) and cloud computing were born, IDC service providers enabled virtual hosting in order to make fuller use of server resources and lower the purchase threshold.

The virtual host function allows you to split a running physical server into multiple "virtual servers". H owever, the technology does not enable the current cloud host technology hardware resource isolation, so that these virtual servers use the physical server's hardware resources, vendors can only limit the size of the hard disk space. For a variety of reasons ,mainly low prices, there are still many enterprises or individual web hosts using the form of virtual hosts to deploy websites.

Apache's virtual host function is the server based on the user requested different IP address, host domain name or port number, the implementation of multiple websites at the same time to provide access to the external services technology, as shown in Figure 10-12, the user requested different resources, the final access to the content of the web page is also different. If you haven't done a website before, you may not understand the principle, and after a while to set up the experimental environment and see the results of the experiment, you will understand.

Again, restore the virtual machine to its original state before doing each experiment to avoid conflicts between multiple experiments.

Figure 10-12 Users request site resources (annex to the original image)