076 | KVM: Powerful Virtualization for Linux

2025-08-08

What is KVM?

KVM (Kernel-based Virtual Machine) is a virtualization technology built directly into the Linux kernel. KVM transforms the Linux kernel into a Type 1 hypervisor (bare-metal), allowing multiple virtual machines to run while leveraging hardware virtualization features of the CPU (Intel VT-x and AMD-V). KVM serves as a core component for many modern cloud platforms, including OpenStack and Red Hat OpenShift.

As part of Linux, KVM is a fully open-source solution, giving developers and system administrators enormous freedom and control over their infrastructure with zero licensing fees.

075 | VMware: The Corporate Virtualization Standard

2025-08-06

What is VMware?

VMware is the undisputed leader and recognized standard in enterprise virtualization. The company that pioneered this technology continues to set the pace in cloud computing and data center management. VMware products such as ESXi (hypervisor) and vSphere (management platform) are known for their reliability, stability, and extensive feature set, making them the primary choice for large organizations where downtime is simply not an option.

Key Features and Advantages of VMware

VMware delivers a comprehensive suite of solutions that address the most demanding virtualization challenges.

MTU Issue on reg.ru and Its Solution via iptables

2025-08-05

Introduction: A Hidden Network Issue

Developers and system administrators using servers on the OpenStack platform (for example, the C*-M*-D* hosting plans from reg.ru) sometimes encounter mysterious network problems. The internet seems to work, but when trying to transfer large amounts of data or establish connections to certain services, requests may hang or fail due to timeouts.

The provider explains this issue as a feature of their infrastructure:

Servers on the OpenStack platform use VxLAN technology, which reserves 50 bytes for service information. Because of this, the maximum transmission unit (MTU) on the server’s main network interface (ens3) is 1450 bytes.

074 | Proxmox VE: A Universal Platform for Virtualization and Containerization

2025-08-05

What is Proxmox VE?

Proxmox Virtual Environment (Proxmox VE) is a powerful and flexible open-source virtualization platform that allows you to manage virtual machines and containers through a single web interface. Proxmox VE is based on the Debian GNU/Linux operating system and uses the KVM hypervisor for full virtualization and LXC for lightweight containerization. Its key advantage is versatility and ease of management, making it a popular choice for both home labs and small to medium-sized businesses.

073 | Introduction to Virtualization: Why It’s Needed and How It Saves Time

2025-08-04

What is Virtualization?

Virtualization is a technology that allows the creation of virtual versions of resources such as servers, operating systems, storage, or networks. It makes it possible to run multiple “virtual machines” (VMs) on a single physical server. Each VM operates as a fully independent computer with its own operating system and applications, while sharing the physical resources of the underlying hardware.

The key component of virtualization is the hypervisor. A hypervisor is software that creates and manages virtual machines, distributing the host machine’s physical resources (CPU time, RAM, disk space, and network interfaces) among them.