Check Virtualization Setup

You are helping the user check if the system is properly set up to run virtualized workloads and remediate any issues.

Your tasks:

Check if CPU supports virtualization:

Intel (VT-x):
```
grep -E "vmx" /proc/cpuinfo
```
AMD (AMD-V):
```
grep -E "svm" /proc/cpuinfo
```
If no output, virtualization is not supported or not enabled in BIOS.
Check if virtualization is enabled in BIOS:
```
sudo apt install cpu-checker
sudo kvm-ok
```
If it says KVM can be used, virtualization is enabled. If not, user needs to enable it in BIOS/UEFI.

Check current virtualization software:

KVM/QEMU:

which qemu-system-x86_64
lsmod | grep kvm

VirtualBox:

which virtualbox
VBoxManage --version

VMware:

which vmware
systemctl status vmware

Docker (containerization):

docker --version
systemctl status docker

Check KVM kernel modules:
```
lsmod | grep kvm
```
Should show:
- kvm_intel (for Intel)
- kvm_amd (for AMD)
- kvm (base module)
If not loaded, try:
```
sudo modprobe kvm
sudo modprobe kvm_intel  # or kvm_amd
```

Install KVM and related tools (if not installed):

sudo apt update
sudo apt install qemu-kvm libvirt-daemon-system libvirt-clients bridge-utils virt-manager

Check libvirt status:

sudo systemctl status libvirtd

If not running:

sudo systemctl enable libvirtd
sudo systemctl start libvirtd

Add user to required groups:
```
sudo usermod -aG libvirt $USER
sudo usermod -aG kvm $USER
```
User needs to log out and back in for group changes to take effect.
Verify user permissions:
```
groups
```
Should include: libvirt and kvm
Check libvirt connectivity:
```
virsh list --all
```
If permission denied, user is not in libvirt group or not logged back in.

Check virtualization networking:

Default network:

virsh net-list --all

If default network is not active:

virsh net-start default
virsh net-autostart default

Bridge networking:

ip link show
brctl show  # if bridge-utils installed

Check nested virtualization (if needed):

For Intel:

cat /sys/module/kvm_intel/parameters/nested

For AMD:

cat /sys/module/kvm_amd/parameters/nested

If shows N or 0, nested virtualization is disabled.

To enable:

echo "options kvm_intel nested=1" | sudo tee /etc/modprobe.d/kvm-intel.conf
# or for AMD:
echo "options kvm_amd nested=1" | sudo tee /etc/modprobe.d/kvm-amd.conf

Then reload:

sudo modprobe -r kvm_intel
sudo modprobe kvm_intel

Check IOMMU for PCIe passthrough (if needed):

dmesg | grep -i iommu

If IOMMU is needed, add to kernel parameters in /etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_iommu=on"
# or for AMD:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash amd_iommu=on"

Then update grub:

sudo update-grub
sudo reboot

Check available storage pools:

virsh pool-list --all

Create default pool if needed:

virsh pool-define-as default dir --target /var/lib/libvirt/images
virsh pool-start default
virsh pool-autostart default

Check system resources for virtualization:
```
free -h
df -h /var/lib/libvirt/images
cat /proc/cpuinfo | grep "processor" | wc -l
```
Recommendations:
- At least 4GB RAM for light VMs
- At least 20GB free disk space
- Multiple CPU cores recommended

Test VM creation (small test):

virt-install --name test-vm \
  --ram 512 \
  --disk size=1 \
  --cdrom /path/to/iso \
  --graphics vnc \
  --check all=off \
  --dry-run

Check for conflicting virtualization: VirtualBox and KVM can sometimes conflict. Check if both are installed:
```
dpkg -l | grep -E "virtualbox|qemu-kvm"
```
VirtualBox kernel modules can conflict with KVM:
```
lsmod | grep vbox
```

Check virtualization acceleration:

ls -l /dev/kvm

Should be:

crw-rw---- 1 root kvm /dev/kvm

Install virt-manager (GUI) if desired:
```
sudo apt install virt-manager
```
Test launch:
```
virt-manager
```
Check for Secure Boot issues: Secure Boot can prevent some virtualization modules from loading:
```
mokutil --sb-state
```
If Secure Boot is enabled and causing issues, user may need to:
- Sign modules
- Disable Secure Boot in BIOS
- Use signed versions

Performance tuning:

Enable hugepages for better performance:

sudo sysctl vm.nr_hugepages=1024
echo "vm.nr_hugepages=1024" | sudo tee -a /etc/sysctl.conf

Check CPU governor:

cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

For virtualization, performance governor is recommended:

sudo apt install cpufrequtils
sudo cpufreq-set -g performance

Report findings: Summarize:
- CPU virtualization support status
- BIOS/UEFI virtualization enabled status
- KVM modules loaded status
- libvirt status
- User group membership
- Network configuration
- Nested virtualization status
- Storage pools status
- Available resources
- Any conflicts or issues
- Recommendations
Provide recommendations:
- Enable VT-x/AMD-V in BIOS if not enabled
- Install KVM/QEMU if not present
- Add user to libvirt and kvm groups
- Set up default network
- Enable nested virtualization if needed
- Configure IOMMU for PCIe passthrough if needed
- Install virt-manager for GUI management
- Allocate sufficient resources
- Resolve any conflicts (VirtualBox vs KVM)
- Performance tuning suggestions
Basic virtualization commands to share:
- virsh list --all - List all VMs
- virsh start <vm> - Start a VM
- virsh shutdown <vm> - Shutdown a VM
- virsh destroy <vm> - Force stop a VM
- virsh console <vm> - Connect to VM console
- virsh net-list - List networks
- virsh pool-list - List storage pools
- virt-manager - Launch GUI
- virt-install - Create new VM from command line

Important notes:

Virtualization must be enabled in BIOS/UEFI
User must be in kvm and libvirt groups
Log out and back in after adding to groups
VirtualBox and KVM can conflict
Nested virtualization is disabled by default
IOMMU required for PCIe passthrough
Secure Boot may prevent module loading
Sufficient RAM and disk space needed
Performance governor recommended for VMs
Check if system is itself a VM before enabling nested virtualization

/virtualization-check-virtualization

Check Virtualization Setup

Your tasks:

Important notes: