Cloud computing reflects current trends in the provision of IT infrastructure, offering unrivaled flexibility, scalability and high availability of systems and applications running in it. On the other hand, dedicated servers often have a performance advantage and are usually the first choice when building IT environments that require complete separation of resources from other users and knowledge of physical storage and processing.
VPS servers running in a virtualization cluster or cloud infrastructure adapt the most important functions of the cloud, although this type of service is not classified as a “real” cloud. In the event of a physical host failure or maintenance work, virtual machines can be moved to another node in the cluster. VPS offers the ability to take pictures or scale resources in the event of an increase in server load. However, much of this marketing, if we take into account the fact that the service is calculated as part of a monthly subscription, and not for the resources consumed, the scaling of the service is to change the server plan to a higher one without the ability to return to the previous configuration, and user data is stored in local RAID arrays, not cloud storage. Worse, hosting providers, as a rule, use rebooking and resale, which makes it difficult to talk about a full guarantee of computational computing resources. Regardless of these shortcomings, VPS services are a serious competition for virtual instances running in the cloud.
Dedicated server resources are fully provided to one client. We can choose from a variety of predefined configurations that we can customize to suit your needs, by changing the type of processor, adding RAM, or plugging in expansion cards.
Dedicated servers are a specialized service that, to a greater extent than VPS or the cloud, allows you to achieve higher performance specific to certain areas of use, for example, when maintaining high-performance databases. I’m talking here about using local RAID arrays that offer high-performance I / O to bypass the SAN network or the ability to use the full bandwidth of network interfaces and the processing power of processors without the costs of the virtualizer.
The cloud offers one important function that is useless to search in VPS and dedicated servers. We are talking here about the possibility of simple, including fully automated scaling of resources, as well as a change in the level of use of server resources. Vertical scaling involves increasing or decreasing the computational resources of the virtual machine, horizontal scaling consists of creating subsequent instances in a cluster, and then evenly distributing traffic between them at the level of the load balancer.
High availability of VPS services is provided by running virtual machines in a virtualization cluster or in a cloud infrastructure. In the event of a failure of one host, the machines are transferred to another active node. In nonclustered environments, the failure of a physical host results in the inaccessibility of all clients.
A dedicated server does not provide any redundancy, although you can implement reliability configurations on two or more physical machines. High availability of dedicated servers can be implemented in many ways, depending on usage scenarios, for example, from load balancing to several equivalent web application servers to implementing virtualization clusters and private clouds to support business applications.
In the case of cloud computing, high availability is constantly included in its definition. All cloud elements — at the computing level, in the data warehouse, and on the network — are multiplied to ensure uninterrupted service and the required level of data security.
Picture Credit: geralt