Knowing what a virtual machine is,and its counterpart, a bare metal server, can improve your cloud experience If you know what the difference between a virtual machine (shared server) and a bare metal server (your very own never shared server) is, you will have the ability to lower your cloud costs, enable right sized security, meet demand and avoid the cost associated with disaster recover. All of which means you will be able to avoid unnecessary cloud expenses, you will know what you are paying for and what you are getting into.
To start, lets look at what a bare metal server is. Simply put, a bare metal server is a PC configured with server software. This software allows other PCs to connect to the bare metal server over the Internet. These PCs can then store their web sites and associated web pages on the server, run applications and software that reside on the server and as well as store text files, spreadsheet files, graphics, audio clips, videos and even large scale databases on the bare metal server.
Although the bare metal server can support many users, that is it can send out the web pages stored in its memory at a very fast rate to different users (clients), it has limitations. If there are too many requests to the server for web page delivery, apps processing or data stored in a database in the server, the server will slow down, that is its users will be left waiting for the bare metal server to respond, the endless spinning circle icon will appear on their screens.
When you sign up for a cloud service, you will have the option to select bare metal servers or virtual machines. When you select the bare metal server option, you will actually get your very own bare metal server that is located in one of the cloud or ISP providers data centers. You are in effect renting your very own physical server that no else can access. For that reason it is expensive. As well, if your traffic suddenly increases, beyond your expectations, your bare metal server may slow down. In this case you could rent another bare metal server, configure and more, but that will take time and increase your cloud costs
Bare metal server rental costs are often by the month or year, not by the day and not by the hour. Costs vary depending on the type of bare metal server you select. Graphic equipped servers are much more expensive. You can expect to pay anywhere between $50 and $500 a month depending on the bare metal server hardware and software configuration you select.
The other alternative to the bare metal server is the virtualized machine. Also known or related to the shared server or the multi-tenant option. This is in general less expensive than the bare metal server. However if you need a server that needs to perform calculations night and day the shared or virtual server may not be the best choice in terms of economics and security.. However, if you are like many users, you and your company often just need to access your data and applications software a few hours a day at most, the virtual machine will most likely be the best economic choice.
So what is a virtual machine? Well, they do come in different varieties, but to put it simply a virtual machine is a shared server and can be called a multi-tenant server. As an analogy, when you elect a bare metal server option, it is equivalent to renting your very own house to place your data, apps and web site on. When you elect the virtual machine cloud option, you are effectively putting your data, applications and web site in an apartment in an apartment complex. More precisely, a bare metal server configured with software, known as hypervisor software, divides the bare metal server, the house into several hundreds of bare metal servers, the apartments in the apartment complex. This means that the virtual machine, the shared server, can support hundreds of tenants, while the bare metal server , the unshared server, only supports one. Both however, can support thousands of clients (visitors), in different degrees and different capacities with each solution having different limitations.
So how is this possible? The virtual machine software, known as a hypervisor, partitions a bare metal server into several smaller virtual servers. A bare metal server in itself has a lot of computer power and a lot of storage capacity. And for most users and applications (workloads) that power and that storage is not needed. That is most users have small workloads, not large workloads. So in effect a virtual machine takes advantage of this fact, that it will service many users with small workloads, and divides up the bare metal resources so that many users with small workloads can access the virtual machine without any obvious effects on wait time or performance.
There are other considerations to consider when deciding on whether or not to select bare metal servers, a virtual machine or a mixture of both for your cloud solution. These include security, disaster recovery and the need for IT support, maintenance and reconfiguration. For now though you have the basics, that is what a bare metal server is and what a virtual machine is.
