Hypervisor – Single Node

A hypervisor, more often referred to as a virtual machine monitor (VMM), is the software that helps create and manage virtual machines by abstracting the hardware resources of a host system. This means multiple virtual machines may run on one single physical server, each having its own operating system and completely isolated from one another.

Virtualization has been a cornerstone of efficient IT operations, helping organizations make the most of their hardware and simplifying every process by straightening the workloads. Hypervisors have played a key role in this transformation by allowing several operating systems to run at once on a single physical machine. Whether the VMS is used for development, testing, or full-fledged enterprise deployments, a hypervisor is a critical layer of software that enables multiple virtual environments to share the resources of a single physical server. This capability underlies modern data centers, cloud computing, and even personal computing configurations.

Need for Hypervisors

In the state of the modern IT infrastructure, hypervisors play a very important role in optimizing resources and operations, and there are many factors that make them important:

1. Resource Optimization: Resource Optimization enables the utilization of hardware with a view of achieving several virtual machines running on a single piece of physical servers. Consolidation further reduces the requirement for additional servers and necessitates fewer servers compared to a non-consolidated environment, thus significantly decreasing costs associated with hardware, up-front and ongoing maintenance, and energy consumption while maximizing the utilization of resources.
2. Isolation: This technology increases security in virtual environments because each VM runs independently. For example, bugs such as software errors or even breaches in security within one particular VM will have no impact on others due to the fact that each VM works separately, delivering a stable and safe operational framework, particularly in multi-tenant environments where numerous users share physical resources.
3. Flexibility and Scalability: With hypervisors, flexibility and scalability are inherent advantages, enabling fast deployment, modification, and decommissioning of VMs. This agility allows organizations to respond quickly to changing workloads and business demands. Testing and development can occur rapidly, and with easy decommissioning, the virtualization level does not become an impediment. As businesses scale, hypervisors make adding resources a smooth affair, allowing IT infrastructure to scale side by side with organizational goals.

How Does a Hypervisor Work?

Hypervisors are a middleman between physical hardware and VMs. They form an important part of virtualization as they allow multiple VMs to be run on one physical server, providing optimal functionality, security, and resource usage. The hypervisor functionality can thus be summarized into the following several critical steps:

1. Resource Allocation: All these fundamental resources, such as CPU, memory, storage, and network access, are assigned by the hypervisor to all VMs. Therefore, the appropriate allocation of the resources makes each virtual machine work effectively.
2. Task Scheduling: It can assign tasks to more than one VM so that it effectively manages workloads across resources as well as even operational needs.
3. Data Flow Management: This process manages the flow of data among VMs and the hardware it resides in so that they can communicate and, more importantly, assures each of its VMs to have a resource allocation without interference from each other.
4. Isolation Maintenance: The hypervisors maintain strict isolation between the VMs, preventing any one virtual machine from accessing or influencing another. Isolation becomes very important for security and stability in multi-tenancy environments where different users or applications share the same physical infrastructure.

Hypervisor Benefits

The hypervisors introduce great advantages for the organization in terms of management and utilization of the IT infrastructure. With virtualization becoming an ever-increasing requirement in any organization in its quest for flexibility and efficiency, the hypervisor has come as a tool that helps in optimum resource management and tangible operational performance.

It provides a strong platform from which the full potential of hardware can be realized within solutions that can address modern computing demands. Some of the major hypervisor benefits include:

1. Cost Efficiency: Cost Efficiency is one of the primary benefits of using hypervisors. By consolidating multiple virtual machines (VMs) onto a single physical server, organizations can significantly reduce both hardware and maintenance costs. This consolidation minimizes the need for additional physical servers, which translates to lower upfront capital expenditures and reduced ongoing operational expenses, such as power and cooling requirements.
2. Improved Resource Utilization: The next key benefit is improved resource utilization. Hypervisors optimize usage of the hardware resources by allowing many VMs to use the same physical hardware. Thus, CPU, memory, and storage utilization get maximized through avoidance of resource waste or underutilization. This way, organizations can do more with their existing infrastructure and thus achieve efficiency as a whole.
3. Scalability: Scalability is very important for growing businesses. Hypervisors will easily provide an organization with the opportunity to scale its infrastructure by adding and removing VMs according to business needs. Scalability permits businesses to rapidly align with a change in workload, scaling up for higher workloads and scaling down for slow times.
4. Ease of Management: Virtualization also extensively improves ease of management. Virtual environments are more manageable compared to their traditional, physical counterparts. Centralized tools are offered by hypervisors for monitoring, updating, and even for backing up VMs which are quite streamlined. This is a simplified complexity and time requirement for IT administrators. They can devote themselves to more strategic activities.
5. Isolation: Finally, the most fundamental benefit of hypervisors is isolation. Each VM runs in its isolated environment, meaning that failures, crashes, or security breaches in one of the VMs would not impact other VMs. Isolation is something essential when maintaining the stability and security of systems, especially for multi-tenant environments where different applications or users are sharing the same physical resources. In general, hypervisors provide a solid foundation for the management of different workloads without sacrificing strict standards of security and performance.

Single Node Hypervisor

One can install hypervisor on a single node as well.   Often small offices can be immensely benefited with this single node hypervisor especially when the organisation can not afford for a specialised IT person.  Simple management, backups, snapshots becomes very very easy.  If something goes wrong, [ on a software level ]  recovery is possible in minimum time.  If the organisation runs with multiple Operating Systems,  without incurring any extra expenses to buy additional hardware, with the help of hypervisor,

Use Cases :  Small / medium Companies, Shop owners, Professionals like CA, Consultants.

Practical way  :  1.  On physical host kept at your location. 2.  Launch it in cloud with dedicated server.

Question :   We are running a single server on a physical host [ bare-metal ].  What are additional advantage in running the single server instance on top of Hypervisor ?  Is it a smart way or dumb way ?

Answer :  Even when you are running a single instance, it is always practical and better to run that instance on the top of Hypervisor due to following reasons.

1.  Your instance is more dependent on specific hardware.  It means you can port the instance on any other hardware without any technical issues.
2. Maintenance become very very easy.
3. You can take a snapshot, backup of instance in no time.
4. You can alter configuration with a few clicks.
5. You can pin point the performance issues, if any, by looking graphs of processor usage, memory usage, disk usage and network usage.

Issues related to Single Node Hypervisor

Almost  none.  As and when the extra capacity is needed, one can always add more nodes and form a cluster.  So it is wise and practical to start with single node hypervisor in almost all cases.

System Requirements

Processor :64 bit, Memory: 64 GB on wards,  Storage : As per user case, Network Interfaces : Two, Cat 6 cabling

Suggested Additional Hardware

UPS, NAS for keeping backup files.

OS required for Hypervosr :  Linux [ open source, no licence required.

Instances possible : Windows – All Version,  Linux – All Versions  – Number of instances possible – depending on the processor and memory available on the host.