13 November 2018

Virtualization software: hypervisors and control panels

Virtualization is the heart of cloud technology. It's everywhere around us. Thanks to it, we can work with different programs online instead of downloading them on a computer; we can rent computing resources instead of buying own equipment. We can work with big data by transferring it to clouds. Smart drones and autonomous robots are well oriented in space because their brains are located in a powerful data center.
Virtualization helps to divide a dedicated server into several virtual ones to cut hardware costs. Virtualization software makes it possible to take full advantage of the technology.

What is virtualization

Virtualization is the allocation of computing resources for isolated processes that run on the same hardware.
It is possible to create a virtual server, storage, or network. Same as a physical server, a virtual one also has disk space, RAM, and a processor. It is also possible to install a chosen OS on it.
Virtualization helps to cut costs and utilize hardware with higher efficiency.
Virtualization cuts costs. An average dedicated server can host about 10 large online-stores or 100 of medium-size websites. It is irrational to use it for one project. However, it won’t be a good idea to run 100 projects on the same server: if one website is hacked — the other websites will be affected as well. This problem can be solved by dividing a physical server into several virtual private servers (VPS).
Hosting providers rent out virtual servers. Infrastructure owners create VPS to host their sites, test software, deploy an internal portal for employees, or CRM. They can also create virtual desktops, proxies and mail servers.
Hypervisors and control panels were created for virtualization management.

Advantages of virtualization

Use hardware more efficient Instead of hosting three different services on three independent servers, it is possible to host them on one. You can use the remaining equipment for other needs or refuse from it.

Reduce workload on staff It is a way easier to maintain several virtual servers than maintaining the same amount of dedicated servers. Virtual servers are cheaper to rent than dedicated ones, so they can also cut your costs.

Increase the speed and flexibility You don’t need to configure hardware and network to deploy a virtual server. You can create and delete it with a few clicks. It saves a lot of time on launching new services or creating a testing environment.

Make services more reliable When you run two different services on independent virtual machines, they don’t affect each other. If one service causes an OS crash or is hacked — the other service will continue working as usual.

Hypervisors

Hypervisors are often called a “thin layer” between a physical server and virtual machines
A hypervisor — is a software that creates and launches virtual machines. The hypervisor makes it possible to run different operating systems on every VM. It distributes computing resources between VMs, isolates them from each other, and allows to turn it on and off independently.
There are hardware and software hypervisors. The hardware hypervisors are considered more productive than software ones.
Hardware hypervisors
Software hypervisors
KVM, Oracle VM Server, Microsoft Hyper-V, VMware ESX.
VMware Workstation, VMware Player, VirtualBox, Parallels Desktop.
There are hybrid hypervisors as well. Sometimes it is hard to define the type of hypervisor. For example, Microsoft Hyper-V can be considered as hardware and software hypervisor at the same time.
Hypervisors are distributed under free and commercial licenses. Oracle VM Server is a paid solution. Microsoft Hyper-V is available free of charge to all users who have purchased a license for Windows Server. The VMware ESX hypervisor has a free edition. KVM is included in the Linux kernel and is distributed for free.

Control panels

Control panels make it more convenient to use hypervisors.
A virtualization control panel is a service where you can manage a hypervisor from a graphical interface. It helps to create virtual machines of the necessary configurations, install different software, configure them and do backups.
Virtualization control panels vary by the hypervisors they work with. We will discuss those panels that work with KVM hypervisor because the commercial hypervisors like Oracle VM Server, Microsoft Hyper-V, and VMware ESX have their own control panels.
KVM is an integral part of Linux kernel, so it is possible to manage it from the console, even without any panel at all. However, using the console requires having at least basic administration knowledge and takes more time even if you are an experienced admin. Please check our Control Panel vs The Console comparison.
KVM virtualization panels: Proxmox, SolusVM, and VMmanager. They solve the same problems in general, but there are some differences:
  1. Proxmox have a limited free edition,
  2. SolusVM can work with OpenVZ and Xen along with KVM,
  3. VMmanager has a modern interface and extensive features for VPS providers.
ISPsystem develops VMmanager, so we will take is as an example to describe the advantages of control panels.

VMmanager 6 — a convenient KVM control panel

VMmanager 6 interface
VMmanager 6 is a modern virtualization control panel. It has a convenient interface and well-thought UX, supports working with images and allows managing multiple clusters even if the servers are located in different physical locations.
VMmanager 6 works both for individual infrastructure owners and providers. It automates every stage of working with VMs, from the moment of creating and configuring to selling them and further management.
VM creation. A user only needs to specify the number of vCPUs, storage and RAM volume, select the OS and applications to install. The panel will do the rest by itself. It takes only 2 minutes to create a VM and install the needed software. If you need a lot of machines of the same type, use the cloning feature or create a custom template and deploy new virtual machines from it. Besides, when you create a VM it is possible to specify how many VMs of this type you need.
Management. VMmanager helps to manage a virtual machine: stop it, restart, reinstall, migrate, clone, run a script, connect via VNC. There is a log of the Tasks where you can find the information who started a certain operation, how much time it took and see the failed tasks if any.
Monitoring. The panel makes it convenient to monitor the virtual machine and nodes. See the load on processors and RAM of the VMs, the available storage amount, check the uptime. Panel admins can see how many resources of the nodes are used, how many virtual machines are created, how many VMs can be created at a certain node.
Selling VPS. VMmanager 6 can be integrated with BILLmanager and WHMCS, so it is very easy to automate selling VMs to customers. Even a specific network configuration of Hetzner data center is not a problem, because VMmanager has native support for Hetzner and allows to resell the services from this data center right from the box.
VMmanager 6 is a modern virtualization control panel.