Files
cozystack/packages/apps/vm-instance
Aleksei Sviridkin c290dee945 fix(vm-instance)!: refuse resources that cannot size the VM
resources.cpu and resources.sockets are typed as quantities, but they
land in domain.cpu.cores and domain.cpu.sockets, which KubeVirt
declares as uint32. The chart cast them with int64, which turns 500m,
1.5 or 1e1 into 0 without an error, and KubeVirt boots a zero core
count as one core. The user asked for half a core and got a one-core
VM with nothing reporting it.

The raw spelling is now decoded as YAML, the way an integer field
reads it, and the render stops unless the result is a positive whole
number that fits in uint32. A leading zero is refused, because YAML
reads 010 as octal 8. The check keys on presence rather than
truthiness, so an unquoted 0 is refused instead of being read as
unset.

Memory gets the same presence check. A quoted "0" was truthy and
rendered requests.memory: "0", while an unquoted 0 was falsy and
dropped, so one quantity took two paths. A zero or negative amount
now stops the render in both spellings.

BREAKING CHANGE: values that used to render now either fail or
render differently. A cpu or sockets that does not decode to a plain
whole number within uint32 (a millicore, suffixed such as 1k,
fractional, zero, negative or leading-zero value), and a zero or
negative memory, fail the next upgrade of the release until the
value is fixed. This includes cpu or sockets set on its own beside an
instanceType, which used to be ignored whatever it held. A spelling
that the int64 cast truncated to 0 but that YAML decodes to a whole
number, such as the exponent 1e1 or the trailing dot 2., used to boot
one core and now sizes the VM with the count it spells, so such a VM
changes size on upgrade.

Assisted-by: LLM
Signed-off-by: Aleksei Sviridkin <f@lex.la>
2026-09-23 11:31:07 +03:00
..
2024-10-16 18:35:30 +02:00
2024-11-04 17:34:40 +01:00
2024-10-16 18:35:30 +02:00
2025-09-24 12:32:37 +02:00

Virtual Machine

A Virtual Machine (VM) simulates computer hardware, enabling various operating systems and applications to run in an isolated environment.

Deployment Details

The virtual machine is managed and hosted through KubeVirt, allowing you to harness the benefits of virtualization within your Kubernetes ecosystem.

Accessing virtual machine

You can access the virtual machine using the virtctl tool:

To access the serial console:

virtctl console <vm>

To access the VM using VNC:

virtctl vnc <vm>

To SSH into the VM:

virtctl ssh <user>@<vm>

Parameters

Common parameters

Name Description Type Value
external Enable external access from outside the cluster. bool false
externalMethod Method to pass through traffic to the VM. string PortList
externalPorts Ports to forward from outside the cluster. []int [22]
externalAllowICMP Whether to accept ICMP traffic to the VM in PortList mode (preserves ping and PMTU discovery). No effect in WholeIP mode. Default true so ping behaves as users expect even when port filtering is in effect. bool true
runStrategy Requested running state of the VirtualMachineInstance string Always
instanceType Virtual Machine instance type. Ignored when resources sizes the VM, which needs whole-number cpu and sockets plus memory; the whole type is dropped then, so any dedicated CPU placement, hugepages, NUMA or realtime settings it carries go with it. While this field is set, a resources block that sizes only part of the VM is rejected outright instead of ignored, so complete it or clear it. string u1.medium
instanceProfile Virtual Machine preferences profile. string ubuntu
disks List of disks to attach. []object []
disks[i].name Disk name. string ""
disks[i].bus Disk bus type (e.g. "sata"). string ""
networks Networks to attach the VM to. []object []
networks[i].name Network attachment name. string ""
subnets Deprecated: use networks instead. []object []
subnets[i].name Network attachment name. string ""
gpus List of GPUs to attach (NVIDIA driver requires at least 4 GiB RAM). []object []
gpus[i].name The name of the GPU resource to attach. string ""
cpuModel Model specifies the CPU model inside the VMI. List of available models https://github.com/libvirt/libvirt/tree/master/src/cpu_map string ""
firmware Firmware and boot configuration (UEFI/BIOS selection, Secure Boot, persistent EFI NVRAM). object {}
firmware.bootloader Bootloader to boot the VM with: "uefi" (OVMF) or "bios" (SeaBIOS). Empty inherits the instanceProfile default. string ""
firmware.secureBoot Enable UEFI Secure Boot. Only applies when bootloader is "uefi". bool false
firmware.efiPersistent Persist EFI NVRAM (e.g. enrolled Secure Boot keys, such as an updated Microsoft UEFI CA) across reboots. Only applies when bootloader is "uefi". On default RWO storage the VM is node-pinned (no live-migration). bool false
resources Resource configuration for the virtual machine. Set whole-number cpu and sockets together with memory to size the VM directly, which overrides instanceType. Alongside an instanceType, a block that sizes only part of the VM is rejected; a whole-number cpu or sockets on its own sizes nothing and is ignored. object {}
resources.cpu Number of CPU cores allocated, as a positive whole number such as 2. Millicore and fractional quantities are rejected at render time, because the value becomes the VM's integer domain.cpu.cores. quantity ""
resources.memory Amount of memory allocated, as a positive quantity such as 8Gi. quantity ""
resources.sockets Number of CPU sockets (vCPU topology), as a positive whole number such as 1. Millicore and fractional quantities are rejected at render time, because the value becomes the VM's integer domain.cpu.sockets. quantity ""
sshKeys List of SSH public keys for authentication. []string []
cloudInit Cloud-init user data. string ""
cloudInitSeed Seed string to generate SMBIOS UUID for the VM. string ""

U Series

The U Series is quite neutral and provides resources for general purpose applications.

U is the abbreviation for "Universal", hinting at the universal attitude towards workloads.

VMs of instance types will share physical CPU cores on a time-slice basis with other VMs.

U Series Characteristics

Specific characteristics of this series are:

  • Burstable CPU performance - The workload has a baseline compute performance but is permitted to burst beyond this baseline, if excess compute resources are available.
  • vCPU-To-Memory Ratio (1:4) - A vCPU-to-Memory ratio of 1:4, for less noise per node.

O Series

The O Series is based on the U Series, with the only difference being that memory is overcommitted.

O is the abbreviation for "Overcommitted".

UO Series Characteristics

Specific characteristics of this series are:

  • Burstable CPU performance - The workload has a baseline compute performance but is permitted to burst beyond this baseline, if excess compute resources are available.
  • Overcommitted Memory - Memory is over-committed in order to achieve a higher workload density.
  • vCPU-To-Memory Ratio (1:4) - A vCPU-to-Memory ratio of 1:4, for less noise per node.

CX Series

The CX Series provides exclusive compute resources for compute intensive applications.

CX is the abbreviation of "Compute Exclusive".

The exclusive resources are given to the compute threads of the VM. In order to ensure this, some additional cores (depending on the number of disks and NICs) will be requested to offload the IO threading from cores dedicated to the workload. In addition, in this series, the NUMA topology of the used cores is provided to the VM.

CX Series Characteristics

Specific characteristics of this series are:

  • Hugepages - Hugepages are used in order to improve memory performance.
  • Dedicated CPU - Physical cores are exclusively assigned to every vCPU in order to provide fixed and high compute guarantees to the workload.
  • Isolated emulator threads - Hypervisor emulator threads are isolated from the vCPUs in order to reduce emaulation related impact on the workload.
  • vNUMA - Physical NUMA topology is reflected in the guest in order to optimize guest sided cache utilization.
  • vCPU-To-Memory Ratio (1:2) - A vCPU-to-Memory ratio of 1:2.

M Series

The M Series provides resources for memory intensive applications.

M is the abbreviation of "Memory".

M Series Characteristics

Specific characteristics of this series are:

  • Hugepages - Hugepages are used in order to improve memory performance.
  • Burstable CPU performance - The workload has a baseline compute performance but is permitted to burst beyond this baseline, if excess compute resources are available.
  • vCPU-To-Memory Ratio (1:8) - A vCPU-to-Memory ratio of 1:8, for much less noise per node.

RT Series

The RT Series provides resources for realtime applications, like Oslat.

RT is the abbreviation for "realtime".

This series of instance types requires nodes capable of running realtime applications.

RT Series Characteristics

Specific characteristics of this series are:

  • Hugepages - Hugepages are used in order to improve memory performance.
  • Dedicated CPU - Physical cores are exclusively assigned to every vCPU in order to provide fixed and high compute guarantees to the workload.
  • Isolated emulator threads - Hypervisor emulator threads are isolated from the vCPUs in order to reduce emaulation related impact on the workload.
  • vCPU-To-Memory Ratio (1:4) - A vCPU-to-Memory ratio of 1:4 starting from the medium size.

Development

To get started with customizing or creating your own instancetypes and preferences see DEVELOPMENT.md.

Resources

The following instancetype resources are provided by Cozystack:

Name vCPUs Memory
cx1.2xlarge 8 16Gi
cx1.2xlarge1gi 8 16Gi
cx1.4xlarge 16 32Gi
cx1.4xlarge1gi 16 32Gi
cx1.8xlarge 32 64Gi
cx1.8xlarge1gi 32 64Gi
cx1.large 2 4Gi
cx1.large1gi 2 4Gi
cx1.medium 1 2Gi
cx1.medium1gi 1 2Gi
cx1.xlarge 4 8Gi
cx1.xlarge1gi 4 8Gi
d1.2xlarge 8 32Gi
d1.2xmedium 2 4Gi
d1.4xlarge 16 64Gi
d1.8xlarge 32 128Gi
d1.large 2 8Gi
d1.medium 1 4Gi
d1.micro 1 1Gi
d1.nano 1 512Mi
d1.small 1 2Gi
d1.xlarge 4 16Gi
gn1.2xlarge 8 32Gi
gn1.4xlarge 16 64Gi
gn1.8xlarge 32 128Gi
gn1.xlarge 4 16Gi
m1.2xlarge 8 64Gi
m1.2xlarge1gi 8 64Gi
m1.4xlarge 16 128Gi
m1.4xlarge1gi 16 128Gi
m1.8xlarge 32 256Gi
m1.8xlarge1gi 32 256Gi
m1.large 2 16Gi
m1.large1gi 2 16Gi
m1.xlarge 4 32Gi
m1.xlarge1gi 4 32Gi
n1.2xlarge 16 32Gi
n1.4xlarge 32 64Gi
n1.8xlarge 64 128Gi
n1.large 4 8Gi
n1.medium 4 4Gi
n1.xlarge 8 16Gi
o1.2xlarge 8 32Gi
o1.4xlarge 16 64Gi
o1.8xlarge 32 128Gi
o1.large 2 8Gi
o1.medium 1 4Gi
o1.micro 1 1Gi
o1.nano 1 512Mi
o1.small 1 2Gi
o1.xlarge 4 16Gi
rt1.2xlarge 8 32Gi
rt1.4xlarge 16 64Gi
rt1.8xlarge 32 128Gi
rt1.large 2 8Gi
rt1.medium 1 4Gi
rt1.micro 1 1Gi
rt1.small 1 2Gi
rt1.xlarge 4 16Gi
u1.2xlarge 8 32Gi
u1.2xmedium 2 4Gi
u1.4xlarge 16 64Gi
u1.8xlarge 32 128Gi
u1.large 2 8Gi
u1.medium 1 4Gi
u1.micro 1 1Gi
u1.nano 1 512Mi
u1.small 1 2Gi
u1.xlarge 4 16Gi

The following preference resources are provided by Cozystack:

Name Guest OS
alpine Alpine
centos.stream10 CentOS Stream 10
centos.stream10.desktop CentOS Stream 10
centos.stream9 CentOS Stream 9
centos.stream9.desktop CentOS Stream 9
centos.stream9.dpdk CentOS Stream 9
cirros Cirros
debian Debian
fedora Fedora (amd64)
fedora.arm64 Fedora (arm64)
fedora.s390x Fedora (s390x)
legacy Legacy Guest
linux Linux Guest
linux.efi Linux EFI Guest
linux.virtiotransitional Linux Virtio Transitional Guest
opensuse.leap OpenSUSE Leap
opensuse.tumbleweed OpenSUSE Tumbleweed
oraclelinux Oracle Linux
rhel.10 Red Hat Enterprise Linux 10 (amd64)
rhel.10.arm64 Red Hat Enterprise Linux 10 (arm64)
rhel.10.s390x Red Hat Enterprise Linux 10 (s390x)
rhel.7 Red Hat Enterprise Linux 7
rhel.7.desktop Red Hat Enterprise Linux 7
rhel.8 Red Hat Enterprise Linux 8
rhel.8.desktop Red Hat Enterprise Linux 8
rhel.8.dpdk Red Hat Enterprise Linux 8
rhel.9 Red Hat Enterprise Linux 9 (amd64)
rhel.9.arm64 Red Hat Enterprise Linux 9 (arm64)
rhel.9.desktop Red Hat Enterprise Linux 9 Desktop (amd64)
rhel.9.dpdk Red Hat Enterprise Linux 9 DPDK (amd64)
rhel.9.realtime Red Hat Enterprise Linux 9 Realtime (amd64)
rhel.9.s390x Red Hat Enterprise Linux 9 (s390x)
sles SUSE Linux Enterprise Server
ubuntu Ubuntu
windows.10 Microsoft Windows 10
windows.10.virtio Microsoft Windows 10 (virtio)
windows.11 Microsoft Windows 11
windows.11.virtio Microsoft Windows 11 (virtio)
windows.2k12 Microsoft Windows Server 2012/2012 R2
windows.2k12.virtio Microsoft Windows Server 2012/2012 R2 (virtio)
windows.2k16 Microsoft Windows Server 2016
windows.2k16.virtio Microsoft Windows Server 2016 (virtio)
windows.2k19 Microsoft Windows Server 2019
windows.2k19.virtio Microsoft Windows Server 2019 (virtio)
windows.2k22 Microsoft Windows Server 2022
windows.2k22.virtio Microsoft Windows Server 2022 (virtio)
windows.2k25 Microsoft Windows Server 2025
windows.2k25.virtio Microsoft Windows Server 2025 (virtio)
windows.2k3 Microsoft Windows Server 2003
windows.2k8 Microsoft Windows Server 2008/2008 R2
windows.2k8.virtio Microsoft Windows Server 2008/2008 R2 (virtio)
windows.7 Microsoft Windows 7
windows.7.virtio Microsoft Windows 7 (virtio)
windows.xp Microsoft Windows XP