Virtual Private Servers (VPSs) exist in a sort of middle ground between cheaper shared hosting and more expensive dedicated servers. This makes them useful for a wide variety of web hosting situations. A VPS may be right for you if any of these following situations apply:
1. You need more performance
Is your website starting to outgrow its shared hosting? Are you users complaining of slow response times? Perhaps it's time to consider moving up to a better level of hosting. Virtual Private Servers are similar to shared hosting in that more than one virtual server can be hosted on a site - which helps keep the price down. But they also tend to have better performance, because each virtual server gets a fixed shared of the host's resources. There's no way for one virtual server to "hog" the resources that other virtual servers on the host need - which is a common problem in shared hosting situations.
2. You need more stability
In a shared hosting environment, many websites are run from a single operating system on the server. Thus, problems with one of these sites can cause problems for the server - which causes problems for all the other sites hosted on that server! Virtualization allows the multiple virtual servers to run on the physical host, and each virtual server has it's own operating system and services. Even if one virtual server crashes, it has no effect at all on the others. Likewise if one virtual server begins to "hang" because of problems with a database (for example) - that virtual server can be safely restarted without affecting the others.
3. You need more security
Websites running on a shared hosting platform are all running within the same operating system, and on the file system. This means that theoretically one shared hosting client could in one way or another affect the files that make up the website of another, or perhaps take advantage of security flaw to somehow affect another client on the server. VPS clients are not as vulnerable to these risks, because the virtualization software prevents any such occurrence. As far as the virtual server's know, they are totally separate from any other virtual servers that may be running on the host.
4. You need more control
If you're running a site in a shared hosting environment, the hosting company is forced to place some restrictions on what can or cannot be done on the server, in order to guarantee quality of server to other clients on the server. For example, you cannot expect the hosting company to allow you to reboot the server whenever you want - it would take down all the other client's websites who are hosted on that server! Likewise, there are many kinds of custom configurations that may be useful to your website, but may adversely affect the other clients, and therefore can't be allowed. If your website or web application needs more control over the environment it's running in, then a VPS may be perfect. You get "root" access to your VPS - at a cheaper rate than a full blown dedicated server!
Aric Watson is a webmaster for NEXCESS.NET, a leading provider of web hosting services including VPS plans.
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