When it comes to cloud computing and virtualization, hypervisor is an important term. To be clear, hypervisor is an entity that can easily host a set of virtual machines, including the trivial conglomerate of information, variables, and database entities. A single hypervisor features a mesh of physical hardware — dedicated towards a single job. In this post, we will be understanding the way a hypervisor works and what all it can achieve. Lastly, we will be looking at the existing options which are often leveraged by the cloud providers — in order to extract the most out of any computing vigil.
In simpler terms, a hypervisor is a typical software or specialized firmware dedicated to hosting sets of physical hardware across multiple, virtual machines. However, the modus operandi changes depending upon the vendor. Some of the examples include Hyper-V from Microsoft and even ESXi from VMware. Regardless of the existing hypervisor, every vendor works in a similar manner — distributing the concerned physical hardware over multiple models and operating platforms.
In terms of segregation, we can classify hypervisors as Type 1 or Type 2 entities — modified for achieving a similar result. However, these options vary when it comes to the structural variables.
Type 1 Hypervisor: Bare Metal
This version is directly installed onto the concerned hardware sans the intervention of an operating platform. Just zero in on the hardware and install the hypervisor of choice. Some of the examples include ESXi and the Hyper-V Server. The best part is a unified access code associated with the Type-1 Hypervisors, offering direct physical access. Operating systems hardly matter when these Type 1 variants are concerned.
Over a period of time, these hypervisors grew in stature and assisted virtualization across mid-frame and mainframe systems. Most of these are morphed, right into the x86 hardware platforms.
Type 1 hypervisors can readily handle the complex hardware functions including oversubscription and a lot more. However, applying these require efficiency and higher skill levels. Most of these come with stringent hardware requirements including extra horsepower and varied server-class modules. While these are perfect for IT operations, using them for petty desktop works might not be a viable option.
Type 2 Hypervisor
These entities are specially designed for working along with the concerned operating platform. The existing Hypervisors include parallels desktop over Mac and the Hyper-V Role over Windows. Lower sets of expertise are required but complex processes cannot be handled with these. Some of the basic tasks which can be taken care of include testing, emulation, and basic development.
There are instances when a particular hypervisor can function as both Type 1 and Type 2 entity. An example would be KVM on Linux which works as Type 2 on being combined to the QUEMU or quick emulator. However, if normalcy is desired — it is prudent enough to opt for a single hypervisor package for a given job.
Peeping into the Public Cloud Vendors
Many vendors are shelling out cloud-based services, and we will be listing a few important ones, with each having Type-1 and Type-2 hypervisors to choose from.
Amazon Web Services: This is the market leader when it comes to cloud-based services, with the largest chunk of IaaS services to look at. Considered as a proprietary platform, AWS works on assumptions and offers negligible premise solutions to work with. So, if a mattress company has set up a cloud-centric infrastructure and the customers are confused as to which is the best bed to buy — using AWS can be the perfect option, as it can help integrate IaaS with online retailing basics. When it comes to the hypervisor, Xen is the existing entity associated with the AWS. Advantages of using the same include efficient para-virtualization and better maturity. Lastly, Xen isn’t associated with the Linux kernel.
Microsoft Azure: Better known for enterprise software like SQL and Exchange, this cloud services provider offers virtualization along with the inclusion of something called as the Azure stack. This platform is the best bet for industries which are looking for a hybrid solution. Out here, we have the Hyper-V as the persisting hypervisor. This is one Linux-based entity that doesn’t come free.
Apart from these, we have several other vendors, including the VMware vCloud, Rackspace, and even the Google Cloud Platform, which offer their own sets of hypervisors for better virtualization. While the Google platform runs KVM — one of the most popular hypervisors out there — ESXi is a proprietary unit of the VMWare interface. Moreover, an organization needs to take care of other options, like the distributed resource scheduler or the DRS for moving particular instances from the hypervisor layer to the cluster.
Lastly, we are slowly moving towards a fairly new term called Docker which is more of an abstraction layer — placed on top of a hypervisor. Most eCommerce firms are opting for cloud-based services based on demographics. However, quite lately the shift has been towards the hypervisor capabilities with several companies offering newer type 1 or type 2 entities to work with.
The trick is to select the best one as per preference.