What is a virtual machine?

A virtual machine - VM for short - is basically a digital replica of a physical computer. Virtual machines can run operating systems and programs, store data, establish network connections and perform many other tasks - without needing their own hardware. Instead, the VM uses virtual resources that are provided by a so-called host system. This is managed by special software, the so-called hypervisor. The virtual machines can be used in a variety of ways, for example for testing new applications, in production and development environments or for operating individual specialized processes.

VMs are a central component of the cloud offering from German provider STACKIT. The STACKIT Compute Engine provides users with powerful and secure VMs that can be used for various use cases. STACKIT operates its data centers exclusively in Germany and Austria and thus meets high data protection requirements and GDPR compliance. Originally developed for in-house use, STACKIT now offers tried-and-tested, flexible IT services as part of the Schwarz Group - from infrastructure such as virtual machines to individual cloud solutions. With STACKIT, companies benefit not only from European data sovereignty, but also from independence from global providers and innovation. Find out everything you need to know about VM below.

• Virtual machine (VM): Software-based replica of a physical computer that runs on a host system and uses its resources such as RAM, CPU and hard disk. The VM is completely isolated from the host and other virtual machines, but can run its own operating system and applications.
• Virtualization: This technology enables the operation of several virtual machines on a single physical server. Virtualization allows hardware resources such as processors or memory to be abstracted and made available to several VMs as virtual resources. In this way, a single computer can operate several independent systems simultaneously.
• Hypervisor: Special software that creates, manages and isolates VMs from each other. The hypervisor distributes hardware capacities to the various VMs. There are type 1 hypervisors that run directly on the hardware (e.g. VMware ESXi) and type 2 hypervisors that are installed on an operating system (e.g. VirtualBox).
• Host: Physical computer or server on which the VMs are operated. It provides the required computing capacity and is managed by the hypervisor.
• Guest: The term guest is used to describe the individual virtual machines that are run on the host. Each guest VM can have its own operating system and applications and is isolated from other VMs and the host system.
• Isolation: Each VM is isolated from each other so that security problems, crashes or errors in one VM do not affect the other VMs. Each VM therefore works independently on the same host system.
• Scalability: This term describes the ability to expand or reduce IT infrastructures flexibly and in line with demand. This allows new VMs to be added flexibly or existing ones to be adapted in order to respond to changing business requirements.
• Acloud provider is a service provider that provides computing resources such as storage space, networks, VMs or cloud solutions as a service via the internet. Cloud providers such as STACKIT use virtualization to offer customers scalable and flexible IT infrastructure.
• Animage is a file that contains the complete state of a VM at a specific point in time. This template is important for quickly creating new VMs with predefined settings and applications. In addition, identical VMs can be quickly created, backed up or restored with an image.
• Virtual private network (VPN): Encrypted connection over the internet that enables secure access to cloud VMs and remote networks. With a VPN, data can be securely exchanged between different locations as if there were a local connection. Encryption ensures that unauthorized persons have no access to the transferred data and that the connection remains confidential.

A virtual machine (VM) is a software-controlled, isolated computer that runs on a physical server and has its own components such as processor, operating system and memory. In a cloud environment, VMs are used to provide computing power efficiently and flexibly: Companies can create, configure or remove any number of virtual servers - without having to operate their own hardware. Each VM works independently of the others and can be equipped with different operating systems and applications. VMs can therefore offer maximum security and flexibility.

Many of today's technologies - such as cloud computing and artificial intelligence - are based on the virtual machine concept. Virtualization decouples software and operating systems from the underlying physical machine. In cloud computing, for example, VMs are used to make the resources of cloud providers' servers available to multiple customers as independent, isolated environments. This creates a multi-tenant cloud architecture in which different customers can access the virtualized resources together - without interfering with each other.

A virtual machine (VM) is a completely isolated, software-supported environment that is operated on a physical computer - the host. A separate operating system, known as a guest operating system, can be installed within this VM. This guest operating system works independently of the host operating system and accesses virtual hardware components such as the processor, memory and network interfaces provided by the hypervisor.

The host therefore provides the physical resources and manages the virtualization environment, while the guest VM operates as an independent unit within this environment. This makes it possible to run several VMs with different operating systems and applications on a single host simultaneously and securely separated from each other. This clear demarcation and isolation of systems is a key feature of virtualization and enables different tasks to be performed flexibly and efficiently on a shared infrastructure.

• Allocate resources optimally: CPU, memory and storage space must be allocated according to the actual requirements of the VM. Too many resources only lead to unnecessary waste, while an undersupply of resources can lead to performance impairments. You should therefore regularly monitor utilization and adjust the configuration if necessary.
• Monitor performance: Use monitoring tools to keep a constant eye on the performance and resource utilization of the VMs. In this way, you can identify bottlenecks in good time and take countermeasures.
• Pay attention to resilience: Distribute VMs across different regions and zones to increase availability and resilience.
• Keep an eye on costs: Choose the optimal VM type for your workload as well as the appropriate size for the workload to minimize costs. Use smaller standard VMs to avoid unnecessary expenditure and regularly monitor your resource utilization.
• Structured management and organization: Use labels and groupings to organize VMs clearly and create reports more easily. This makes it easier to find resources as well as to manage them.
• Create regular backups: Perform continuous backups to prevent data loss and ensure fast recovery in the event of an emergency.

Virtual machines (VMs) are software-supported computers that run on a physical computer and offer an independent, isolated environment. They access the resources of the host computer, such as the processor, hard disk space and RAM, and enable different operating systems and applications to run in parallel. A particularly important product in the field of virtualization is the virtual desktop: Here, a VM is provided as a personal desktop environment so that users can access their personal workstation from anywhere.

The execution of virtual machines is made possible by the hypervisor. This manages the hardware resources and ensures that several VMs can be operated simultaneously on a single physical computer. This allows companies to run different applications, products and environments on the same physical infrastructure, for example for testing, production or development.

Cloud providers offer many products of VM-based solutions, including specialized VM types for servers, compute-intensive graphics software and virtual desktops. Thanks to STACKIT's flexibility and variety of products, resources can be allocated in a targeted and needs-based manner and different environments can be controlled efficiently - a significant advantage for an innovative IT landscape.

What are the cost benefits of the pay-as-you-go model for virtual machines?

The pay-as-you-go model means that companies only pay for the resources they actually use. This eliminates the need for high initial investments and there are no unwanted costs for unused capacity. Billing is transparent and flexible, so that IT expenditure can be optimally adapted to actual business requirements.

How does STACKIT protect virtual machines?

STACKIT protects VMs with a holistic security concept: access from the Internet is deactivated by default ("security by default") and can only be enabled in a targeted manner. Network and system firewalls can be flexibly adapted to individually control and secure access rights and data traffic. For particularly sensitive applications, STACKIT provides confidential servers that use hardware-based encryption and isolation to securely fulfill even highly sensitive workloads and regulatory requirements in the cloud. In this way, STACKIT combines maximum flexibility with customized protection measures and modern security standards - for reliable and secure operation of virtual machines.

How can virtual machines be customized?

Virtual machines can be individually adapted to requirements, especially in the cloud. You can change the VM size at any time, provision or remove new machines within minutes and allocate resources dynamically depending on your workload.