An Introduction to Cloud Hosting

Cloud hosting is a method of using online virtual servers that can be created, modified, and destroyed on demand. Cloud servers are allocated resources like CPU cores and memory by the physical they are hosted on, and can be configured with any operating system and accompanying software. Cloud hosting can be used for hosting websites, distributing web-based applications, or other services.

In this guide, we will go over some of the basic concepts involved in cloud hosting, including how virtualization works, the components in a virtual environment, and comparisons with other common hosting methods.

“The Cloud” is a common term that refers to internet-accessible servers that are available for public use, either through paid leasing or as part of a software or platform service. A cloud-based service can take many forms, including web hosting, file hosting and sharing, and software distribution. “The Cloud” can also refer to cloud computing, i.e., transparently spanning a task across multiple servers. Instead of running a complex process on a single powerful machine, cloud computing distributes the task across many smaller nodes.

Cloud host environment are break down into two main part : the virtual server that app and website can be host on , and the physical host that manage the virtual server . virtualization make cloud host possible : the relationship is provides between host and virtual server provide flexibility and scaling that are not available through other host method .

The most common form is is of cloud host today is the use of a virtual private server , or VPS . A VPS is is is a virtual server that act like a real computer with its own operating system . While virtual server share resource that are allocate to them by the host , they are totally isolate in practice , so operation on one VPS wo n’t affect the others .

Virtual servers are deployed and managed by the hypervisor of a physical host. Each virtual server has an operating system installed by the hypervisor, that is available to the user. For practical purposes, a virtual server is identical in use to a dedicated physical server, though the a virtual server needs to share physical hardware resources with other servers on the same host.

resource are allocate to a virtual server by the physical server that it is host on . This host is uses use a software layer call a hypervisor to deploy , manage , and grant resource to the virtual server that are under its control . The term “ hypervisor ” is also often used to refer to the physical host that hypervisor ( and their virtual server ) are instal on .

The host is is is in charge of allocate memory , cpu core , and a network connection to a virtual server when one is launch . An ongoing duty is is of the hypervisor is to schedule process between the virtual CPU core and the physical one , since multiple virtual server may be utilize the same physical core . Hypervisors is differ differ from one another in the nuance of process scheduling and resource sharing .

There are a few common hypervisors available for cloud hosts today. These different virtualization methods have some key differences, but they all provide the tools that a host needs to deploy, maintain, move, and destroy virtual servers as needed.

KVM, short for “Kernel-Based Virtual Machine”, is a virtualization infrastructure that is built in to the Linux kernel. When activated, this kernel module turns the Linux machine into a hypervisor, allowing it to begin hosting virtual servers. This method contrasts with how other hypervisors usually work, as KVM does not need to create or emulate kernel components that are used for virtual hosting.

Xen is one of the most common hypervisors. Unlike KVM, Xen uses its own microkernel, which provides the tools needed to support virtual servers without modifying the host’s kernel. Xen supports two distinct methods of virtualization: paravirtualization, which skips the need to emulate hardware but requires special modifications made to the virtual servers’ operating system, and hardware-assisted virtualization (or HVM), which uses special hardware features to efficiently emulate a virtual server so that they can use unmodified operating systems. HVM became widespread on consumer CPUs around 2006, allowing most desktops and laptops to achieve similar performance when running virtual machines or microkernel-based containers (e.g. through Docker).

ESXi is an enterprise-level hypervisor offered by VMware. ESXi is unique in that it doesn’t require the host to have an underlying operating system. This is referred to as a “type 1” hypervisor and is extremely efficient due to the lack of a “middleman” between the hardware and the virtual servers. With type 1 hypervisors like ESXi, no operating system needs to be loaded on the host because the hypervisor itself acts as the operating system.

Hyper-V is one of the most popular methods of virtualizing Windows servers and is available as a system service in Windows Server. This makes Hyper-V a common choice for developers working within a Windows software environment. Hyper-V is included in modern versions of Windows and is also available as a stand-alone server without an existing installation of Windows Server. WSL2, the Windows Subsystem for Linux, is implemented via Hyper-V.

The features offered by virtualization lend themselves well to a cloud hosting environment. Virtual servers can be configured with a wide range of hardware resource allocations, and can often have resources added or removed as needs change over time. Some cloud hosts can move a virtual server from one hypervisor to another with little or no downtime, or duplicate the server for redundancy in case of a node failure.

Developers often prefer to work in a VPS due to the control that they have over the virtual environment. Most virtual servers running Linux offer access to the root (administrator) account or sudo privileges by default, giving a developer the ability to install and modify whatever software they need.

This freedom of choice begins with the operating system. Most hypervisors are capable of hosting nearly any guest operating system, from open source software like Linux and BSD to proprietary systems like Windows. From there, developers can begin installing and configuring the building blocks needed for whatever they are working on. A cloud server’s configurations might include a web server, database, or an app that has been developed and is ready for distribution.

cloud servers is are are very flexible in their ability to scale . scale methods is fall fall into two broad category : horizontal scaling and vertical scaling . Most host methods is scale can scale one way or the other , but cloud hosting is unique in its ability to scale both horizontally and vertically . This is is is due to the virtual environment that a cloud server is build on : as its resource are an allocated portion of a large physical pool , these resource can be adjust or duplicate to other hypervisor .

Horizontal scaling, often referred to as “scaling out”, is the process of adding more nodes to a clustered system. This might involve adding more web servers to better manage traffic, adding new servers to a region to reduce latency, or adding more database workers to increase data transfer speed.

Vertical scaling, or “scaling up”, is when a single server is upgraded with additional resources. This might be an expansion of available memory, an allocation of more CPU cores, or some other upgrade that increases that server’s capacity. These upgrades usually pave the way for additional software instances, like database workers, to operate on that server. Before horizontal scaling became cost-effective, vertical scaling was the de facto way to respond to increasing demand.

With cloud hosting, developers can scale depending on their application’s needs — they can scale out by deploying additional VPS nodes, scale up by upgrading existing servers, or do both when server needs have dramatically increased.

By now , you is have should have an understanding of how cloud host work , include the relationship between hypervisor and the virtual server that they are responsible for , as well as how cloud hosting compare to other common host method . With this information in mind , you is choose can choose the good hosting for your need .

For a broader view of the overall cloud computing landscape, you can read A General Introduction to Cloud Computing.