The Ghost Operator's Signal
Virtualization is an aging superstar.
It was the hero – decades ago.
Containers lived only on ships.
Clouds painted just the sky.
Hypervisors sprout from necessity.
To segment.
To conceal.
To control.
Then the market turned diluted.
“Market-ready” hypervisors emerged from the fog.
KVM stood.
Silent.
Watching.
When managing virtual machines (VMs) in a Linux environment, using Logical Volume Manager (LVM) with Kernel-based Virtual Machine (KVM) provides several benefits. LVM offers flexibility and control over storage allocation, while KVM, combined with virsh, offers a robust virtualization solution. This guide will walk you through the process of setting up LVM logical volumes for your KVM guests using virsh.
KVM supports a variety of storage types, each catering to different performance and feature requirements. The Raw format is simple and offers high I/O performance but lacks advanced features like snapshots. QCOW2 is more feature-rich, supporting snapshots, compression, and encryption, though it has higher CPU overhead and slightly lower performance. LVM (Logical Volume Manager) offers good performance and easy resizing with thin provisioning, though it can be complex to manage. Network-based storage solutions like iSCSI and NFS provide scalability and shared access, with iSCSI offering block-level and NFS file-level access, both supporting live migration and snapshots. Distributed storage systems like Ceph and GlusterFS are highly scalable and fault-tolerant, ideal for large environments, but require significant setup. Finally, ZFS stands out for its advanced data integrity and management features, making it suitable for environments where robustness is crucial. Each of these storage types supports essential features like live migration and snapshots, enhancing KVM’s flexibility in various use cases.
Continue reading “KVM Storage Support and Features”
A serial console provides a text-based interface for accessing a system, especially when graphical interfaces are unavailable or network connections are down. It allows you to interact with the system using a terminal program, even during boot sequences or critical failures. Here are some scenarios where serial consoles prove beneficial.
Continue reading “Serial Console in KVM”
For system administrators looking to automate deployments, using Kickstart files for automated installations can be a highly efficient approach. This lesson will show you how to install Rocky Linux 9 on a KVM virtual machine using a Kickstart file and the virsh command-line tool.
Snapshots are a powerful feature of KVM that allow you to capture the state of a virtual machine (VM) at a specific point in time. This capability is valuable for system administrators and developers who need to create temporary backups, test changes, or recover from errors. In this lesson, we’ll explore how to manage KVM snapshots using the virsh command-line tool on a Linux server.
KVM storage volumes are virtual disk images that can be assigned to virtual machines. They are stored on the host system and presented to the guest as virtual hard drives. The most commonly used image format for KVM storage volumes is qcow2 (QEMU Copy-On-Write 2). qcow2 is a sparse format that only allocates disk space as needed, allowing multiple volumes to efficiently share the same base image using copy-on-write. This saves disk space compared to raw disk images. qcow2 also supports features like snapshots, encryption, and compression.
Storage pools in KVM virtualization are a way to centrally manage and organize storage resources for virtual machines. A storage pool is a designated area of storage, such as a directory, partition, or network-based storage, that is set aside for use by KVM virtual machines. Once a storage pool is created and started, storage volumes can be defined within the pool and assigned to VMs.
Continue reading “Creating and Managing KVM Storage Pools Effectively”
Migrating just a couple of virtual machines from other virtualization platforms to KVM is easy. Virtualbox uses the Virtual Disk Image (.vdi) format. You can clone the vdi image to a RAW image format using vboxmanage. This way you will not alter your original virtual image file. Then QEMU provides the necessary tools to convert the RAW image to the qcow2 format. Qcow2 is QEMU’s Copy On Write image format.
KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko.
QEMU’s system emulation provides a virtual model of a machine (CPU, memory and emulated devices) to run a guest OS. It supports a number of hypervisors (known as accelerators) as well as a JIT known as the Tiny Code Generator (TCG) capable of emulating many CPUs.
libvirt is a toolkit to manage virtualization platforms.
Continue reading “I Migrated to KVM+QEMU on Debian 12”Hyper-V is the virtualization hypervisor technology of Microsoft. There are different versions of Hyper-V, and we can use the desktop version on our Windows 10 or Windows 11. It is similar to VMWare Workstation Pro or VirtualBox, though its feature set is quite limited.
Continue reading “Using Hyper-V on Windows 10 (Updated on 2023. 03. 05.)”If we want a cool personal lab environment, then we have to use cool tools and technology. Virtual machines are one of the best inventions for learning and practicing IT in isolated environments. We can simulate and test Operating System changes, kernel modifications and even network configurations from our chair on our PC or notebook. Let’s build a basic test lab!
Continue reading “How to install and manage VMWare Workstation Pro virtual machines?”VMWare is a famous name in virtualization technology. If you work in IT it is impossible that you don’t know about the VMWare products. A lot of companies use the vSphere infrastructure with vCenters and ESXi hosts. On the other end of their products there are the home users and small businesses. We can use the Workstation Player for free for non-commercial use of course, but the Workstation Pro has more powerful features that can help us building a personal home lab.
Continue reading “How to install VMWare Workstation Pro on Windows 10?”
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