Choosing the Right Virtualization Platform: Proxmox vs. KVM Explained

In the context of virtualization technology,  the key to deployment success may not be just choosing the most popular platform, but rather by choosing the one that best  suits your business needs. KVM and Proxmox are two prominent examples of virtualization platforms, each with its own unique advantages for handling virtual machines. This article examines the features and strengths of each of them that are likely relevant to you, and the key differences between them.

What is KVM and how Does It Work?

KVM also known as Kernel-based Virtualization Machine is open-source software technology that can be installed on Linux machines to create and manage virtual machines (VMs) that run independently of each other.

KVM can be integrated with any Linux machine powered by a CPU that allows virtualization extensions. It then transforms the Linux kernel into a bare-metal/Type 1 hypervisor, connecting the physical hosting hardware with each of the independent virtual machines.

Understanding The KVM Hypervisor

The KVM Hypervisor, a Type 1 hypervisor, ensures seamless interactions between the physical hardware and the virtual machines (VMs). It provides each VM it controls with all the services of a physical system, including virtual input & output systems and virtual hardware such as processor, memory, network cards, and storage. In other words, each VM models the actual computer.

The KVM hypervisor supports a wide range of guest operating systems, including Linux distributions, Windows, Haiku, macOS, Solaris, and AROS. It also allows for live migration, making it possible for administrators to transfer active VMs to different hosts without experiencing service disruption.

A KVM-centered virtualized environment is managed using tools like Libvirt and Qemu. QEMU is used both to emulate hardware devices and to efficiently manage the creation of VMs, while Libvirt is primarily used for monitoring and controlling VMs on KVM.

Benefits Of Using KVM For Virtual Machines

KVM is considered a top choice for managing virtual machines because of its amazing features and benefits. This section explores some of the features and benefits that make KVM a top choice for managing virtual machines.

• Security

Virtual machines managed using KVM are covered by Linux OS security features, which include Security Enhanced Linux (SELinux) and AppArmor. These tools help to ensure the independent operation of each VM, which prevents interference between virtual machines while also strengthening data privacy and governance.

• High Performance

All KVM operating systems use Linux’s sophisticated scheduling and memory management, allowing for more optimized processing and input/output usage across the VMs being managed. KVM uses hardware extensions such as AMD-V and Intel VT-x, which allow for a very efficient virtualization environment. In addition, KVM’s support for multiple VMs and extensive memory spaces makes it capable of handling both small and enterprise-level workloads efficiently.

• Stability

KVM is powered by a mature source code (Linux Kernel), which offers a solid foundation for enterprise-level applications. Linux Kernel has been used in several business applications over a long period of time and is well supported by an open-source community.

• Flexibility

KVM works well with many hardware setups and, as such, can offer several options to businesses during installations. With KVM, server admins can effectively allocate resources such as memory or storage to any VM. It also allows for thin provisioning, which makes it possible for resources to be allocated to VMs only when required.

• Supports Multiple Operating System

Within the Linux kernel, KVM allows for a virtualization area, making it possible for multiple operating systems, like Windows and BSD, to run as guest operating systems on a host machine. This is often made possible with the integration of QEMU.

Integration of KVM into the Linux Kernel

KVM was merged into the Linux kernel in 2007, transforming Linux into a versatile hypervisor. Making KVM a kernel module seamlessly integrates into Linux’s existing framework, taking full advantage of its memory, scheduler, management, and security features. This enables advanced virtualization features and also ensures efficient allocation of resources among VMs. The integration removes the need to install external hypervisors and also allows KVM to benefit greatly from the Linux ecosystem in terms of security, performance optimizations, maintenance, and updates.

KVM Architecture And Components

KVM is a kernel module that is directly integrated into the Linux kernel, making it a type 1 processor. KVM uses the hardware virtualization capabilities of modern processors (Intel VT-x and AMD-V) to manage several VMs on a single host system. Its architecture includes:

• The Host Operating System: is essentially the Linux operating system running on actual hardware. The host operating system is responsible for managing resources such as memory, CPUs, and Input/Output devices.
• KVM Kernel Module: KVM serves as the main hypervisor, creating a virtualization environment by transforming the Linux kernel. KVM is an interface (/dev/kvm) that merges with user-space tools to manage VMs. The module enables memory management, with support for virtual memory techniques and CPU virtualization using hardware extensions.
• QUEMU: The quick emulator QUEMU is a user-space application that integrates with KVM to model hardware devices for VMs to ensure near-native performance. It is also useful for modeling input/output operations and managing the lifecycles of VMs.
• Virtual Machines: Each guest OS operates in an independent virtual environment created by KVM and QUEMU.
• Virtual Hardware Components: These consist of virtual CPUs (modeled after the host’s physical CPU), virtual memory, and virtual input/output devices.
• KVM Management Tools: include essential tools like libvirt and virsh, which are used in the monitoring and effective management of KVM-based virtual machines.

Hardware Requirements For KVM

When considering the KVM hardware requirements for a successful virtualization experience, note the following factors:

Processor Requirements

• Virtualization Extensions: The CPU must allow hardware virtualization extensions. Examples of CPUs that guarantee optimal performance include Intel VT-x (Intel virtualization technology) and AMD-Virtualization.
• Sufficient Cores & Threads: The more cores and threads your processor has, the better it can manage multiple VMs simultaneously.

Memory (RAM): Every VM takes up a portion of the host’s RAM, meaning the RAM needed for an efficient virtualization experience depends on the number of VMs you intend to manage and their collective resource requirements. It is generally advised to allocate at least 1-2GB of RAM to each virtual machine. Note that you must also make provisions for sufficient RAM for the host server’s operating system and KVM hypervisor.

Storage: Adequate storage space is required for the host OS, KVM software, and the virtual disk image for each VM. Luckily, KVM allows for several storage options, including Storage area networks (SANs), Network-attached storage (NAS), and local disk drives. Note that the choice and speed of storage selected plays a vital role in the performance of the Virtual Machines.

Network Interface Cards (NICs): To ensure a strong line of communication between your virtual machines and the outside world, a reliable network connection is a must. At least 1 NICS is required for the host machine, but multiple NICs are often used to separate management, storage, and virtual machine traffic to achieve the best performance and security.

Motherboard And BIOS: To effectively and securely handle the VMs, the server’s motherboard must be able to support virtualization technology and have its BIOS settings optimized for hardware virtualization extensions.

Cooling And Power Supply: Simultaneously running multiple VMs is most likely to overtax the server’s cooling system and power supply. Be sure to have sufficient cooling mechanisms in place and enough power to handle the extra workload generated by the VMs.

What is Proxmox and What are its Key Features?

Proxmox can best be described as an open-source virtualization platform that simplifies the management process of VMs, storage, and network configurations. It uses 2 main virtualization technologies: KVM (Kernel-based Virtual Machine) for full virtualization and LXC (Linux Containers) for lightweight virtualization. Proxmox was originally created for enterprise-level environments that need large virtualization features and a flexible and expandable system.

Key Features

• Server virtualization: Proxmox uses a free source code, released under GNU AGLv3, which gives users the ability to freely use the software and check out the source code at any time. It also gives users the opportunity to contribute to the project.
• Container-based Virtualization: Proxmox allows container-based virtualization, which functions as an alternative to full-machine because I shares the host system’s kernel.
• Clustering: Proxmox can be expanded to a large set of clustered nodes, which are often fully integrated and work with default installation. These clusters are responsible for ensuring both fault tolerance and load balancing, allowing VMs and containers between nodes with minimal downtime.
• High Availability: Proxmox’s design supports high availability. This means that, when a node in a particular cluster goes down, the VMs or containers hosted on that node move to the next available node automatically, preventing a major service disruption.
• Central Management: Proxmox’s command line, web-based management, and application programming interface make it easy to manage the tasks of the data center.
• Web-based Management Interface: Its web-based management interface makes Proxmox very easy to use. The web-based management interface allows the user to perform all the required management tasks using the integrated graphical user interface (GUI), eliminating the need for a separate management tool. The web interface is accessible from any modern browser and can provide an overview of the task history and system logs for each node. With this feature, a user can manage a whole cluster from any node without the need for a separate manager node.
• Live/Online Migration: Proxmox’s live/online migration feature enables it to move active VMs from one cluster node to another with no downside or effect noticeable to the end-user. Admins can launch this process either from the web-based or command line, minimizing downtimes in instances when the host system must be taken offline for maintenance.
• Supports Multiple OS: Proxmox integrates well with several guest operating systems, including specific versions of Windows, Linux, BSD, and Solaris. This feature makes Proxmox a great platform choice for different types of workloads and developing environments.
• Proxmox Backup Server Integration: Proxmox’s backup server integration ensures efficient, secure, and reliable backups for VMs, containers, and host systems. Proxmox allows for incremental backups, which use block-level storage optimization to minimize both storage and back-up times. Integrating the backup server also enables data encryption on the client side, rendering your backed-up data impenetrable to attackers.
• Extensive Security: Access to every Proxmox user system is protected by two-factor authentication (2FA), as well as role-based access control (RBAC). There is also a built-in firewall for managing network traffic and securing resources.

Exploring The Proxmox Virtual Environment

Proxmox VE is more than just a virtualization tool: it is a multifunctional platform that allows for a wide range of use cases, from hosting web applications to managing containers for microservices. Although originally designed for enterprise needs, Proxmox VE is capable of adapting to meet the needs of diverse IT environments, from small businesses to educational institutions. Proxmox VE is often used where resource optimization, scalability, and ease of management are high priorities. It is especially known for developing hyper-converged infrastructures, supporting edge computing, and implementing disaster recovery solutions. Additionally, Proxmox’s integration capabilities ensure a seamless connection with existing systems, which helps in improving the efficiency of its overall IT operations.

Proxmox VE includes interesting workflows, such as the automation of tasks using APIs and the creation of templates, which, when understood, can enhance efficiency. Proxmox also benefits from an active and robust user community that significantly improves its ecosystem. This includes the availability of plugins, tutorials, and forums that help users discover new ways to optimize and extend their use of the platform.

Management Tools Available In Proxmox

To effectively manage the resources available at its disposal, Proxmox offers different tools to help simplify tasks ranging from basic management to advanced networking and storage solutions. Some of them include:

Proxmox Web Interface

The Proxmox web interface is a powerful, but user-friendly, management tool that enables administrators to control and monitor the entire system from a web browser. This GUI delivers a detailed overview of the entire cluster, VMs, containers, storage, and network settings. Its features include resource allocation, VM and container management, live migration, snapshots, and backups. Conveniently, this tool is easy to manage remotely, as it can be accessed from any device with a browser.

Proxmox Command Line Interface (CLI)

Because Proxmox’s Command Line Interface can perform more tasks than those available in the GUI, it was designed for advanced users. Proxmox uses standard Linux tools like pvecli and pct (for LXC containers) to interact with the system. Two of the major uses of the CLI are in automating tasks and integrating Proxmox with other tools.

Proxmox Cluster Management

Proxmox supports clustering and can manage multiple nodes from a single interface using the Proxmox cluster management tool. This tool can facilitate the creation and maintenance of HA (high-availability) clusters. It also ensures that the VMs and containers are distributed across different nodes for better performance.

Storage Management Tools

Proxmox provides several storage management tool options to efficiently manage different types of storage backends. These tools support local, shared, and distributed storage solutions and are capable of:

• Setting up storage pools, volumes, and access permissions
• Allocating and managing disk spaces for VM, containers, and backups
• Moving storage between nodes in the cluster without interrupting services

By allowing both traditional and advanced storage settings, Proxmox gives administrators the flexibility to choose the solution that best suits their needs.

Monitoring Tools

Proxmox has in-built monitoring tools that provide real-time insights into the performance metrics of the system. These tools enable administrators to monitor CPU usage, memory consumption, disk I/O, and network activity. They provide visual representations of resources over time, detailed system events logs, and can be set up to provide alerts for specific events (such as hardware failures).

API and Automation Tools

Proxmox provides a robust API (REST API) for administrators who are looking to automate tasks and integrate its system with other ones. The API allows access to all nearby features available in the Proxmox GUI and CLI. Proxmox’s API is often integrated with automation tools like Terraform and Ansible.

Networking Options And Configurations

The Proxmox VE’s networking is an important aspect, responsible for facilitating communication among host systems, virtual resources, and external networks. Here is a breakdown of the network options and configuration within Proxmox:

Network Interface

Proxmox supports user-configurration of physical network interfaces on the host system. These interfaces could be Ethernet cards or virtual interfaces used by containers or VMs. Note that physical interfaces are typically assigned to the host’s main network connections, while the virtual interfaces are connected to physical network interfaces or to isolated virtual networks.

Bridged Networking

Bridged networking is a very common option in Proxmox. It allows VMs to be connected to the same network as the host system, making them easily accessible on the network. By default, Proxmox creates a bridge interface (vmbr), which serves as a virtual switch and can be assigned to VMs. This bridge interface is typically created on the host system, making it easy for the host interface to connect to it, allowing the VMs to share the same IP network.

Network Address Translation (NAT)

NAT makes it possible for virtual machines to access external work using private IP addresses. This network option is perfect when there is no need for the VMs to be accessible from the external network. The VMs are placed behind a NAT router, which maps their private IP to the host’s public IP. The host acts as the gateway to the outside world.

Virtual Local Area Network (VLAN)

With Proxmox, virtual machines can be installed on specific VLANs to isolate and organize the network. This process, called ‘VLAN tagging,’ is an effective way to improve network management through the local segmentation of traffic. The VMs in Proxmox are linked to VLANs through a VLAN-bridge interface.

Bonding Interface

A bonding interface, otherwise known as link aggregation, is best described as a network option that allows several network interfaces to be combined into a single logical one. This helps to improve bandwidth and reduces duplication. The bonding modes available on Proxmox include Mode 0 (Round-robin), Mode 1 (Active backup), and Mode 4 (LACP).

IPv6 Configuration

Proxmox supports the updated internet protocol IPv6 and allows its users to configure their VMs and containers with IP version 6 addresses to enable communication within modern networks. IPv6, unlike its predecessor, addresses space exhaustion and inefficiencies in both routing and network management. It also eliminates the need for NAT and was designed with in-built security. The configuration of IPv6 in Proxmox can be done at both the physical host level and within virtualized environments.

Proxmox Backup And Recovery

Proxmox VE ensures the safety and availability of its data at all times, especially in the event of system failures, hardware issues, or accidental loss of data. It can achieve this by providing different tools and features that facilitate reliable backup and recovery processes for VMs, containers, and whole clusters.

Here is  a closer look at Proxmox’s backup and recovery functionalities:

Proxmox Backup Types: Proxmox VE supports several types of backups, making it possible for administrators to choose the backup options that adequately meet their needs in terms of environment and workload. The major backup types available in Proxmox include:

• Snapshot Backup: This makes it possible to capture the exact state of a VM or container at any particular moment.
• Stop Mode Backup: allows for consistent and reliable file backups.
• Live Backup: facilitates backups while the virtual machines are running. It captures the VM’s state online without affecting its performance.

Backup Scheduling: Proxmox VE has a built-in scheduler that is useful for automated backups, making it possible for administrators to pre-schedule system backups. It is typically managed using either the Proxmox GUI or CLI. With the Proxmox scheduler, a user can specify his/her preferred frequency of backups (daily, weekly, monthly), the time, as well as the retention period for each backup in the backup automation setup. This reduces human intervention in the process and ensures the maintenance of regular backups. Proxmox’s backup retention policies can be modified to automatically delete older backups to free space.

Storage Backups: Proxmox allows backups to be stored in various locations. Types of backup storage supported by Proxmox include:

• Local Storage: Local disks connected to the Proxmox host;
• Network Storage: Network shares like NFS (Network File System), CIFS (Common Internet File System), and SMB (Server Message Block); and
• Cloud: Integration with cloud storage services such as S3-compatible storage.

Incremental Backups: Proxmox eliminates the need for the system to copy the entire data every time the system is backed up. Through incremental backups, only the modifications made since the last backup are saved, whichreduces backup size.

Backup Monitoring And Notifications: Proxmox VE offers monitoring and notification functionalities that help administrators informed about backups. For example, there are monitoring tools in the Proxmox web interface that give users a clear view of the history and current status of backups, ensuring their regular performance and that no failures occur unnoticed.

Proxmox Backup Server (PBS): The PBS is a dedicated Proxmox backup solution designed to handle backups efficiently. To ensure file safety, it includes such features as deduplication, file compression, and encryption to ensure the file’s safety.

Bacula Enterprise: Bacula Enterprise is a third-party backup solution that functions as an alternative to PBS. It is extremely secure and has a natively integrated Proxmox module designed to provide rapid recovery performance. Bacula offers higher granular control over backups than PBS, making it the preferred choice for specific business and regulatory requirements. It also supports a wider range of cloud providers and hybrid cloud setups, making it easier to ensure seamless backups to various destinations.

Here is a comprehensive list of some of the features Bacula Enterprise offers for Proxmox:

• Snapshot-based Online Backup: Bacula systems allow for the snapshot of Proxmox VMs while they are running. This helps to significantly reduce the downtime of a VM during the backup process.
• Full Image-level Backup: Bacula provides complete data protection by enabling full-image backup support for Proxmox VMs.
• Incremental Backups: The Bacula system helps to conserve Proxmox backup storage by supporting incremental backups. This feature ensures that only the changes made after the last backup process are saved and stored.
• Proxmox Cluster Integration: Bacula helps to simplify the backup for Proxmox VMs by supporting the automatic scanning of Proxmox clusters to create backup configurations for each VM.
• Flexible Backup Strategies: Bacula provides Proxmox users flexibility by offering two different approaches to backups. These include the creation of backup files and the installation of the Bacula Enterprise File Daemon.

KVM Backup and Restore

KVM may lack integrated backup systems, but it offers a strong foundation for implementing backup strategies.

Snapshots For VM Backups: KVM allows for snapshots (Disk & System) that capture the state of a VM at a specific time. These snapshots typically include the VM’s disk, image, memory state, and configuration, enabling the user to easily revert to the snapshot if needed. The snapshots are created on KVM with tools like virsh, which is useful only for short-term backups.

Backup Using External Tools: KVM leverages external tools like Libvirt, Rsync, Bacula, and Amanda to facilitate their backups. KVM users can also make use of custom scripts to manage backups. These scripts enable them to combine commands like virsh dumpxml to save VMs.

Live Backup Options: Using QUEMU and viable storage space like ZFM, KVM can allow its virtual machines to keep running while their disks are being backed up. This way, KVM can create snapshots of the VM’s disk and stream those snapshots to the backup location.

Backup Storage Options: KVM integrates well with multiple storage backends and thus offers flexibility when choosing when to store backups. Commonly used storage options include local storage, network-attached storage (NFS or CIFS/SMB), and cloud storage.

Bacula Enterprise: Bacula Enterprise is a scalable third-party backup and recovery software solution that integrates with KVM to deliver robust backup features. Some of these features include:

• Full Backup Support: Bacula ensures full backups of KVM virtual machines, keeping an exact record of the VM’s entire state, including the metadata and disk images. It also allows backups of KVM guest VMs without installing software on specific clients.
• Scalability: Bacula’s KVM backup system has a powerful deduplication engine (Global Deduplication Engine) which helps to optimize backup storage space and has also proven its ability to handle petabyte-scale environments.
• Incremental Backups: Bacula saves backup time by supporting incremental backups, ensuring that only new data is backed up and added to the preexisting one. This reduces both backup storage time and backup storage requirements.
• Auto-detection Capability: Bacula’s auto-detection capability eliminates the need to manually determine which VM(s) to back up when data changes occur.
• File-level Recovery: Bacula’s high-level granularity allows it to recover individual files within a VM’s backup without having to restore the entire VM.
• Supports Online Backups: Bacula allows backups of KVM virtual machines while they are running. This way, disruptions to both users and applications can be avoided.
• Backup Scheduling: Bacula Enterprise offers KVM virtual machines powerful backup automating capabilities, enabling admins to schedule single or multiple VM backups at once. The system is also automated to retry failed backup jobs or send trigger alerts for intervention.
• Exceptionally high security levels: Bacula has a unique architecture that increases protection levels over standard solutions, and security is further increased by running its core server on Linux. Immutibility, air gapping, encryption and security interfaces all come with multiple configuration options, reflecting Bacula’s development for its use by large military and government reseach organizations.

Comparing Proxmox and KVM Features

Proxmox Features

Proxmox is an open-source complete virtualization platform that uses both container-based and full virtualization solutions to support both KVM and LXC. Proxmoxoffers a central management and detailed web-based interface that simplifies the management of VMs, containers, storage, and networking. Proxmox supports HA clustering, live migration, and enterprise-level backup solutions with its built-in Proxmox Backup Server. The platform provides strong storage integration and support for tools like Ceph, NFS, ZFS, and ISCSI. It also includes its own firewall and network configuration tools. In addition, Proxmox benefits from a vibrant online community of users that contributes to its ecosystem.

KVM (Kernel-based Virtual Machine) Features

KVM is a highly efficient virtualization solution that is built directly into the Linux kernel. It supports a wide range of guest operating systems, including Linux, Windows, and BSD, offering hardware-assisted virtualization with Intel VT or AMD Technologies. With the right external tools, KVM can support features like live migration, snapshots, and resource allocation. KVM integrates seamlessly with various management tools like Libvirt, Proxmox, and OpenStack to offer an expandable and versatile virtualization environment.

Performance Metrics: Proxmox vs. KVM

Response Efficiency

Proxmox integrates KVM with additional tools for managing virtual environments, making it highly responsive even with enterprise-level workloads. Its interface and clustering features allow it to efficiently monitor and allocate resources while also reducing response time in managing VMs. KVM, on the other hand, is a lightweight hypervisor that is known for its near-native performance as a result of its direct integration with the host system (Linux). However, it requires additional manual configuration to achieve the same level of management efficiency as Proxmox, which could considerably increase Proxmox’s response time when handling multiple VMs.

Memory Performance

Proxmox improves KVM’s memory performance with in-built memory management tools such as dynamic memory allocation and ballooning, ensuring optimal usage across VMs. This makes Proxmox capable of handling memory-intensive work without manual intervention. In contrast, KVM’s memory relies on the configuration of the host system. KVM delivers excellent performance with the aid of the user’s manual configuration, using features like Transparent Huge Pages (THP).

CPU Throughout

Proxmox leverages KVM’s capabilities with high CPU throughout, while adding support for features like CPU-pinning and real-time scheduling through its user-friendly interface. With these features, Proxmox provides better control and automated distribution of CPU resources across VMs. KVM also delivers excellent CPU throughout because of its kernel-level integration and support for hardware-assisted virtualization. However, unlike Proxmox, an optimized CPU throughout KVM requires advanced knowledge of Linux and manual configuration.

I/O Performance Of The File System

KVM provides excellent I/O performance by integrating with the host kernel. Sophisticated storage backends and manual setup of the file system produce even higher I/O performance results.  Proxmox on the other hand, uses features like FS integration and storage replication to optimizes I/O performance, which improves the speed and reliability of VMs.

Overall Performance

Both Proxmox and KVM are excellent performers. KVM’s lightweight performance and direct integration with the Linux kernel offer near-native performance. This makes it an incredible virtualization option for users who are comfortable with manual configuration and tuning. Proxmox addsmore features, further enhancing its performing capabilities. It is more suitable for users seeking whole, user-friendly solutions in search of streamlined management and efficiency.

Choosing the Right Platform Based on Use Cases

Proxmox Use Cases

Proxmox VE is an excellent virtualization management option, best-suited for enterprise-level needs, due to its centralized interface that manages both VMs and containers efficiently. It is superior in its ability to develop HA clusters, which ensures minimal downtime of critical applications in cases of failures, by automatically migrating them to healthy nodes. Proxmox is also a strong choice for businesses that prioritize data security, as it provides robust backup and recovery capabilities with tools like Proxmox Backup Server, which protects data and ensures data recovery by enabling incremental backups. It also supports VDI (Virtual Desktop Infrastructure), which allows organizations to deliver secure and expandable virtual desktops, making it the perfect choice for private clouds and remote work setups.

KVM Use Cases

KVM is a powerful hypervisor modified for high-performance virtualization directly on bare-metal hardware. It is best suited for workloads like database servers and real-time applications that require computational efficiency. Developers and QA teams often use KVM for creating stand-alone environments in which to test and debug software, optimizing features such as snapshots and iterative testing. Because of its flexibility, advanced networking, and storage capabilities, it can also be integrated into platforms like OpenStack and used in cloud infrastructure.  Because of its ability to provide resource isolation and strong security, KVM is also a strong choice for hosting and multi-tenancy.

Key Differences Between KVM and Proxmox

KVM and Proxmox are both open-source virtualization solutions that are built on Linux, butyet provide different features. Here are a few differences between the two systems using different metrics:

Architecture

KVM is a kernel-based hypervisor that is built directly into the Linux kernel. It uses the features possessed by the host operating system to provide hardware virtualization. Proxmox VE, on the other hand, is a complete virtualization management solution that uses KVM in combination with container-based technologies.

High Availability (HA)

Proxmox VE includes built-in high availability (HA) that  enables that automatic migration of VMs and containers to other nodes in cases of hardware failure. KVM also includes this feature, but requires additional configuration to achieve similar functionality.

User Interface

Proxmox VE offers a web-based interface that enables users to manage VMs, containers, storage, and networking resources from a centralized structure. To perform the same function on KVM requires users to interact with command-line tools or third-party management tools.

Community And Support

KVM and Proxmox both have active communities of users and provide support through forums and community-driven resources. However, Proxmox provides more commercial support options and enterprise-level features for users who need professional assistance.

Networking

Proxmox VE and KVM both support advanced networking features like VLAN tagging, bridged networking, and software-defined networking. The only difference is that KVM might require extra manual configuration and set up.

How Do You Migrate Between KVM and Proxmox?

Moving VMs between KVM and Proxmox VE is a straightforward that is highly dependent on prior planning and execution.

How to Migrate Between KVM and Proxmox

Step 1: Plan Your Migration

• VM(s) Inventory: First. identify the VMs to be migrated, noting their disk sizes and dependencies.
• Backup VMs: Create backups for all the listed VMs to help prevent loss of data during migration.
• Confirm compatibility: Ensure that both environments support the same CPU architecture and hardware virtualization features.

Step 2: Prepare Proxmox

• Install Proxmox VE.
• Configure the Proxmox storage to which the VMs will be moved.
• Ensure that Proxmox and the KVM host devices have similar network bridges.

Step 3: Export VMs From KVM

• Shut down the VM on the KVM host to ensure consistency.
• Export the disk to a compatible format such as qcow2 or raw.
• Copy the exported disk to the Proxmox server.

Step 4: Create the New VM In Proxmox

• Using either the Proxmox command line or web interface, generate a new virtual machine in Proxmox.
• Review the hardware configuration of the KVM virtual machine to make sure it matches.
• Remove the disk created during the VM setup in Proxmox and import the transferred disk.
• Update the VM configuration to support the newly imported disk.

Step 5: Configure and Test the VM

• Adjust the boot order and ensure that the correct disk is set as the primary boot device.
• Connect the network interface to the correct bridge.
• Start the VM.
• Confirm that the VM has booted successfully.
• Inspect the application and network to confirm operational functionality.
• When the VM does not boot, you may need to install virtIO drivers or make adjustments.

Step 6: Post-Migration Cleanup

• Delete the original VM files after the migration.
• Monitor the performance of the VM on Proxmox to ensure it operates as expected.

Tools Used In Migrating Between KVM And Proxmox

• Quemu-ing: Used for converting disk images from one format to another.
• Virsh: used to shut down or export VMs before migration.
• Scp (Secure Copy Protocol): Safely transfers VM disk files from the KVM host to the Proxmox server.
• Proxmox VM Manager: Used to create, configure, and manage VMs through the command line.
• Nano/Vim/VI: Used in editing VM configuration files on Proxmox.
• Tar/ gzip: Used in compressing large VM disk files for faster transfers.
• Ping/ssh: Used to verify connectivity and access between the KVM host and Proxmox server.

Storage Options: KVM vs. Proxmox

KVM Storage Options

The options for storage available in KVM include local storage (hard drives or SSDs), network-attached storage (NAS), and storage area networks (SAN). KVM also supports storage formats used to create disk images like raw, qcow2, and vodka. Additionally, to create enough room for performance and capacity flexibility, KVM enables administrators to configure VM storage using either direct disk access or network-based solutions like NFS or ISCSI.

Proxmox Storage Options

Like KVM, Proxmox fully supports the use of diverse storage options for managing both its VMs and container data. Examples of these options include local storage types (e.g. ZFS, LVM), directories, and network-based storage solutions like NFS, ISCI, and Ceph. Proxmox also allows the use of its web interface for storage management. This option makes it possible for Proxmox users to create and manage storage pools for their virtual environments.

How To Set Up A Virtualization Environment With KVM?

Creating a virtualization environment with KVM has prerequisites which involve you first verifying that the system is updated and supports hardware virtualization (Intel VT or AMD-V). After confirmation, the next course of action is to install the KVM and its associated tools such as quemu-kvm, libvirt, and virt-manager. After installation, confirm that the KVM module is loaded by running the code ‘’1smod|grep kvm’’.  In the next prompt, add your user to the libvirt group and restart the system. Once the system is back up, start the libvirt service at boot with the command;‘’sudo systemvtl enable libvirtd’’. Afterward, use the virt-manager to launch the GUI for managing VMs or virsh commands if you prefer the command-line management interface. After this configuration, you can now create and manage VMs as a user.

Step-By-Step Guide On Installing KVM

1. Check Hardware Virtualization Support: To verify if your system supports hardware virtualization, run the command “egrep -c ‘(vmx |svm)’ /proc/cpuinfo”. If the outcome of the command turns out to be greater than 0, it means that your system supports hardware virtualization.
2. Install KVM And The Required Packages: To install KVM, together with it’s the required tools on a system, run this command; “ sudo apt install qemu-kvm libvirt-bin virt-manager bridge-utils”
3. Verify KVM Installation: The next step is to confirm the KVM installation through this command: “1smod|grep kvm”
4. Add User To The libvirt Group: The addition of a user to the libvirt group enables you to manage virtual machines without the use of root privileges. To add, run the command below and then log out and then, back in to apply changes. The command code is: “sudo usermod -aG libvirt $(whoami)”
5. Start And Enable The Libvirt Service: Start the libvirt service and ensure it starts automatically on boot. To do this, add the command: “sudo systemtcl start libvirtd sudo systemtcl enable libvirtd”
6. Install Virtual Machine Management: To get a graphical interface, you have to install the virt-manager which handles the management of the VMs. To install the virt-manager, run the command: “sudo apt install virt-manager”
7. Create A Virtual Machine: Launch the virt-manager to create a virtual machine.
8. Verify installation: After the KVM has been installed, you can verify its smooth operation by checking the Virtual Machines created. To check: “sudo virsh list –all”

Configuring Virtual Machines On KVM

When configuring VMs on KVM, there are 2 main factors that are often considered; installation of packages and networking.

• Installation Of Packages: The important packages that are needed to be installed for KVM include tools like qemu-kvm, libvirt, and virt manager. Before installation, it’s important that you specify the OS installation media (such as an ISO file) to be used, and also allocate CPU, memory, and storage resources. Furthermore, you have to define the virtual disk being imputed. Note that KVM supports multiple virtual disk formats and in so doing, provides its users with options to select the format that best suits their needs.
• Networking: is very important when configuring VMs. It involves the process of selecting a network type like NAT (for internet access) or bridged networking.

After choosing, the virt-manager is then used to attach the VM to the desired network interface during setup.

Use Command-Line For KVM Management

Using the command line for KVM management is a preferred choice for advanced users that requires both flexibility and automation. There are important tools such as virsh and virt-install which can be integrated with KVM to perform tasks like creating and managing virtual machines. For example, with virsh, a user can list, start/stop VMs, and even edit configurations directly. The command-line method is especially powerful for scripting and managing VMs in enterprise-scale environments.

How To Set Up A Virtualization Environment With Proxmox

In order to create a virtualization environment with Proxmox, you have to start by downloading the VE ISO image from the Proxmox official website. Then you would need to create a bootable USB drive using tools like Rufus or Etcher. The next step involves that you boot your server from the USB and then follow the installation wizard’s guide to set up the software and configure the system disk network and time zone settings. After installation, access the Proxmox web interface by entering the server’s IP address into a browser (use ‘’https://server-ip>:8806). Set your password during installation and then login with the root account. Finally, update the system and configure the settings like storage and networking as required. With this steps carried out, you can now create and manage Proxmox VMs and containers directly from the web interface.

Creating And Managing VMs In Proxmox

Virtual machines are easy to create and even easier to manage on Proxmox because of its central management feature. To get started on creating a VM, follow these steps:

1. Access the Proxmox web interface by opening a browser and entering “’https://server-ip>:8806”.
2. Login with your root account and password
3. Go to Datacenter and then Storage to select your storage (e.g local)
4. Click “content”, and then “upload” to add the ISO file for the OS you want to install in the VM.
5. On the top right corner, click on “Create VM”
6. Fill in the General tab and then enter a name for the VM that has been auto-assigned
7. Click on “next” to move through the tabs to configure details like OS, System type (Default selected), CPU allocation, Memory, and Network Customization
8. Review the settings you made and click on “Finish” to create the VM

To manage Proxmox VMs, follow these steps:

1. Select your newly created panel in the left panel and click on “Console” to open the VM console
2. Click on “start” to boot the VM and follow the installation steps for the selected operating system
3. To start, stop, or restart the VMs, the buttons are at the top of the page
4. To monitor the resources such as the memory, CPU, and disk usage, click under the Summary tab
5. To modify the resources e.g. reallocate disk allocations, click the “Hardware” tab and restart it
6. The snapshots can be taken using the Snapshots tab
7. To manually migrate VMs between nodes in Proxmox clusters, click the Migrate tab
8. You can explore the Cloud-init and Templates for automated configurations

Using LXC Containers With Proxmox

LXC containers in Proxmox offer a lightweight and efficient avenue to virtualize applications. To start would require downloading and updating Proxmox while ensuring the availability of adequate storage configured for containers. Next is to navigate to Datacenter>Storage in the Proxmox web interface. Select your storage and download an LXC template from the Templates section. To create a container, click on Create CT, assign a unique container ID, set a hostname, and configure resources like CPU, memory, and storage. Select the downloaded template and configure network settings like a connectivity bridge. After creating the container, access and start it via the web console or SSH for application development. With these steps, you can control the containers from the Proxmox interface same as the VMs are managed.

Cost Analysis And Licensing

KVM Cost Analysis & Licensing

Cost Analysis: KVM is a free, open-source included as part of the Linux kernel. There are no licensing fees or additional costs for its use, making it very cost-effective for individuals and organizations. The primary costs associated with KVM stem from the underlying hardware and optional management like Red Hat Management for example, or any other GUI-based solutions which may attract extra expenses.

Licensing: KVM is licensed under the GNU (General Public License), which ensures that it remains free and open-source. This licensing allows users to freely use, modify, and also distribute the software.

Proxmox Cost Analysis & Licensing

Cost Analysis: Proxmox VE is also free and open-source. While the main platform is free, Proxmox offers additional paid subscriptions that start at 105 pounds per year and per CPU socket for professional support, access to the enterprise repository, and timely updates. It is important to note that these subscriptions are not mandatory.

Licensing; Proxmox VE is licensed under the GNU Affero General Public License (AGPL) v3, allowing full access to the source code. This license promotes transparency and collaboration, allowing users to modify and distribute the software. However, modifications have to be shared under the same license so as to maintain its open-source nature.

Proxmox Subscription Model

The Proxmox subscription model allows access to the enterprise repository. This includes thoroughly tested updates, technical support, and stable packages. The subscription tiers include: Basic, Standard, Premium, and Community. Not that users without a subscription can still access the no-subscription repository which still provides updates but may be less tested.

Total Cost Of Ownership

The total cost of ownership of virtualization solutions like Proxmox and KVM includes the direct and indirect costs incurred over its life cycle. It also takes into account the hardware requirements, optional licensing, or subscription fees.

Proxmox Total Cost Of Ownership

Proxmox TCO is relatively low as a result of its open-source nature. While the software is free, the TCO includes other factors such as hardware optional enterprise subscription, and infrastructure costs like storage, power, and networking. However, Proxmox’s built-in features help to further reduce the costs.

KVM Total Cost Of Ownership

The TCO for KVM is equally low owing to its open-source nature and inclusion in the Linux Kernel, removing the licensing fees. The cost that arises stems mainly from the hardware, storage, and optional management tools integrated into the hypervisor.

Support Options

Proxmox Support Options: Proxmox offers different support options depending on the user’s needs. While the core platform is free, Proxmox provides a paid subscription model for businesses that require professional help. Users in need without subscription can benefit from community support which is active through forums and the Proxmox wiki.

KVM Support Options: KVM does not have its own support system. The users, however, can solicit help via KVM’s robust community, including forums, mailing lists, and online resources. Businesses requiring advanced help can leverage third-party companies like Red Hat for the professional services they need.

FAQs

How Many VMs Can I Run On A Single Host?

The number of virtual machines (VMs) you can run on a single host is dependent on the host’s hardware resources. This includes the CPU, memory, storage as well as the resources of each VM. Theoretically, you can have several hundreds of VMs on a high-performance server, but practical limitations like storage and CPU determine the maximum number that a host server can actually run.

Can Proxmox Use KVM As Its Hypervisor?

Certainly! Proxmox already uses KVM as its hypervisor for managing VMs. KVM is well integrated into Proxmox VE, allowing efficient virtualization of both Linux and Windows VMs.

Can You Use Containers With Both KVM And Proxmox?

Yes. KVM and Proxmox support container-based virtualization but in different ways. Proxmox natively supports LXC for container-based virtualization through its web interface. KVM on the other hand, allows container-based virtualization by leveraging container management tools like Docker or LXC.