KVM

KVM virtualization

Introduction

Component	Description
kvm	Kernel module for CPU and memory virtualization
QEMU / qemu-kvm	IO virtualization and device emulation, interacts with kvm via IOCTL
libvirt	Daemon and API for managing virtualization platforms (KVM, Xen, etc.)
virsh	CLI tool based on libvirt
virt-install	CLI tool for creating KVM virtual machines
virt-manager	Virtual machine UI management tool
virt-viewer / virt-clone / virt-top / virt-v2v	Display, clone, monitor, and migrate VMs

How To Use

# Check hardware virtualization support
lscpu | grep Virtualization

# Install
dnf install qemu-kvm qemu-img
dnf install libvirt libvirt-python libvirt-client virt-install virt-manager

# Start libvirtd
systemctl start libvirtd
systemctl enable libvirtd
lsmod | grep kvm

# Option: Install bridge-utils
dnf install -y bridge-utils
vim /etc/sysconfig/network-scripts/ifcfg-ens192
vim /etc/sysconfig/network-scripts/ifcfg-br0
systemctl restart network
ip addr show br0

# Create vm
# option1: install initial vm by UI
virt-manager
# option2: install initial vm by iso
osinfo-query os # search os variant
virt-install \
  --name=template-ubuntu-22.04-base \
  --vcpus=2 \
  --ram=4096 \
  --disk path=/var/lib/libvirt/images/template-ubuntu-22.04-base.qcow2,size=20 \
  --cdrom=/tmp/ubuntu-22.04.iso \
  --os-variant=ubuntu22.04 \
  --network network=default \
  --graphics spice
qemu-img convert -O qcow2 -c template-ubuntu-22.04-base.qcow2 template-ubuntu-22.04.qcow2
qemu-img info template-ubuntu-22.04.qcow2
# option3: install vm by qcow2 template
virt-install \
  --name=vm-test \
  --import \
  --vcpus=2 \
  --ram=4096 \
  --disk path=/var/lib/libvirt/images/rockylinux9.5.qcow2 \
  --os-variant=ubuntu22.04 \
  --graphics spice \
  --network network=default \
  --noautoconsole

# Manager
virsh net-list --all
virsh list --all
virsh start vm_name
virsh autostart vm_name
virsh shutdown vm_name
virsh destroy vm_name
virsh undefine vm_name --remove-all-storage
virsh console vm_name
virsh edit vm_name