Talos Linux can run in local QEMU virtual machines, providing a full boot experience similar to bare metal or cloud deployments. This is useful for testing boot processes, upgrades, and platform-specific features.
Overview The QEMU provisioner provides:
Full VM boot process (BIOS or UEFI)
PXE boot support for testing network boot
Multiple disk configurations (SATA, NVMe, virtio)
CNI-based networking
TPM emulation
DHCP/TFTP/DNS services
Load balancer for control plane HA
QEMU clusters provide the most production-like local environment but require more resources than Docker.
Prerequisites
QEMU installed (qemu-system-x86_64 or qemu-system-aarch64)
Linux or macOS host
At least 8GB RAM (2GB per node minimum)
talosctl installedCNI plugins (automatically downloaded)
Install QEMU Linux (Ubuntu/Debian)
Linux (Fedora/RHEL)
macOS
sudo apt update sudo apt install qemu-system-x86 qemu-utils
Quick Start Create a local QEMU cluster:
talosctl cluster create --provisioner qemu
This creates:
1 control plane node (default)
VM network with DHCP and load balancer
State directory at ~/.talos/clusters/<cluster-name>
Cluster Configuration Multi-Node Cluster talosctl cluster create \ --provisioner qemu \ --name my-cluster \ --controlplanes 3 \ --workers 2
Resource Configuration talosctl cluster create \ --provisioner qemu \ --controlplanes 3 \ --cpus 2 \ --memory 4096 \ --disk 20480
Boot Options UEFI Boot
BIOS Boot
PXE Boot
# Enable UEFI (default on arm64) talosctl cluster create \ --provisioner qemu \ --with-uefi
QEMU Provisioner Architecture The QEMU provisioner creates a complete infrastructure:
// From pkg/provision/providers/qemu/create.go func ( p * provisioner ) Create ( ctx context . Context , request provision . ClusterRequest , opts ... provision . Option ) ( provision . Cluster , error ) { // 1. Create CNI network p . CreateNetwork ( ctx , state , request . Network , options ) // 2. Create load balancer for control plane p . CreateLoadBalancer ( state , request ) // 3. Create DNS server p . CreateDNSd ( state , request ) // 4. Create control plane VMs nodeInfo , _ := p . createNodes ( ctx , state , request , request . Nodes . ControlPlaneNodes (), & options ) // 5. Create DHCP server (for PXE) p . CreateDHCPd ( ctx , state , request ) // 6. Create worker VMs workerNodeInfo , _ := p . createNodes ( ctx , state , request , request . Nodes . WorkerNodes (), & options ) // 7. Create PXE VMs (if requested) pxeNodeInfo , _ := p . createNodes ( ctx , state , request , request . Nodes . PXENodes (), & options ) }
Boot Methods Disk Boot (Default) Boot from disk image:
talosctl cluster create \ --provisioner qemu \ --disk-image-path /path/to/disk.raw
ISO Boot Boot from ISO:
talosctl cluster create \ --provisioner qemu \ --iso-path /path/to/talos.iso
PXE Network Boot The provisioner includes built-in PXE infrastructure:
// From pkg/provision/request.go type NodeRequest struct { PXEBooted bool TFTPServer string IPXEBootFilename string }
Create PXE boot cluster:
talosctl cluster create \ --provisioner qemu \ --controlplanes 1 \ --workers 0 \ --extra-boot-kernel-args talos.platform=metal
Advanced Configuration UEFI Options Configure UEFI boot:
talosctl cluster create \ --provisioner qemu \ --with-uefi \ --extra-uefi-search-paths /usr/share/OVMF
TPM Emulation Enable TPM 2.0:
talosctl cluster create \ --provisioner qemu \ --with-tpm2
This requires swtpm package:
# Install swtpm sudo apt install swtpm swtpm-tools # Ubuntu/Debian sudo dnf install swtpm swtpm-tools # Fedora/RHEL
Custom Disk Configuration Configure multiple disks:
machine : disks : - device : /dev/vda partitions : - size : 1GB mountpoint : /var/lib/etcd
Network Configuration Custom CIDR
Custom MTU
Multiple Networks
talosctl cluster create \ --provisioner qemu \ --cidr 192.168.100.0/24
Networking Details CNI Network The QEMU provisioner uses CNI networking:
# CNI config directory (default) ~ /.talos/cni/
Load Balancer Built-in load balancer for control plane:
// From pkg/provision/providers/vm/loadbalancer.go type LoadBalancer struct { Listener net . Listener Backends [] string }
Automatically proxies traffic to control plane nodes on port 6443.
DHCP Server For PXE boot support:
// From pkg/provision/providers/vm/dhcpd.go type DHCPd struct { Listener * net . UDPConn TFTPServer string IPXEBootFilename string }
DNS Server Local DNS resolution:
// From pkg/provision/providers/vm/dnsd.go type DNSd struct { Listener * net . UDPConn Nodes map [ string ] netip . Addr }
VM Configuration Options CPU and Memory talosctl cluster create \ --provisioner qemu \ --cpus 4 \ --memory 8192
Disk Options Single Disk
Multiple Disks
NVMe Disks
talosctl cluster create \ --provisioner qemu \ --disk 20480
Architecture # ARM64 VMs talosctl cluster create \ --provisioner qemu \ --arch arm64 # AMD64 VMs (default) talosctl cluster create \ --provisioner qemu \ --arch amd64
Testing Features Bad RTC Test time-related issues:
talosctl cluster create \ --provisioner qemu \ --bad-rtc
This sets the RTC to a time in the past to test time sync.
IOMMU Enable IOMMU for testing:
talosctl cluster create \ --provisioner qemu \ --with-iommu
Managing Clusters List Clusters talosctl cluster show --provisioner qemu
Access Nodes # Get cluster info talosctl cluster show # Access node talosctl -n 10.5.0.2 version
Destroy Cluster talosctl cluster destroy \ --provisioner qemu \ --name my-cluster
Cluster State Cluster state is stored in:
~/.talos/clusters/<cluster-name>/ ├── controlplane-1/ │ ├── disk.raw │ └── state.yaml ├── worker-1/ │ └── ... └── clusterstate.yaml
Boot Order Control boot order:
// From pkg/provision/request.go type NodeRequest struct { // DefaultBootOrder overrides default boot order "cn" (disk, then network) DefaultBootOrder string // "cn" or "nc" (network first) }
Kernel Arguments Add extra kernel args:
talosctl cluster create \ --provisioner qemu \ --extra-boot-kernel-args "talos.platform=metal console=ttyS0"
Configuration Injection HTTP Injection (Default)
ISO Injection
# Config served via HTTP talosctl cluster create --provisioner qemu
Troubleshooting VM Console Access # View VM console socat -,rawer,escape=0x1d unix-connect:~/.talos/clusters/ < cluster-nam e > /controlplane-1/console.sock
Check VM Process Network Issues # Check CNI network sudo ip link show sudo ip addr show talos0 # Test connectivity ping 10.5.0.2
Disk Issues # Check disk image qemu-img info ~/.talos/clusters/ < cluster-nam e > /controlplane-1/disk.raw
Logs # Cluster creation logs talosctl cluster create --provisioner qemu -v # Node logs talosctl -n 10.5.0.2 logs machined
KVM Acceleration Enable hardware acceleration:
# Check KVM support lsmod | grep kvm # Verify KVM device ls -l /dev/kvm
QEMU automatically uses KVM when available.
CPU Pinning For better performance, consider CPU pinning in production-like tests.
Disk I/O Use native AIO for better performance:
# Uses virtio-blk with native AIO by default
Differences from Docker Feature QEMU Docker Boot Full BIOS/UEFI Container start Kernel Talos kernel Host kernel Storage Virtual disks Volumes/Bind mounts Networking CNI/Bridge Docker network PXE Boot Supported Not applicable Resource overhead Higher Lower Production similarity High Medium
Next Steps
Bare Metal Deploy to physical servers
Upgrades Test upgrade procedures
