# Virtual Machine (simple)

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.

- Docs: [KubeVirt User Guide](https://kubevirt.io/user-guide/)
- GitHub: [KubeVirt Repository](https://github.com/kubevirt/kubevirt)

## Accessing virtual machine

You can access the virtual machine using the virtctl tool:
- [KubeVirt User Guide - Virtctl Client Tool](https://kubevirt.io/user-guide/user_workloads/virtctl_client_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                                                                                                | Value        |
| ------------------------- | ---------------------------------------------------------------------------------------------------------- | ------------ |
| `external`                | Enable external access from outside the cluster                                                            | `false`      |
| `externalMethod`          | specify method to passthrough the traffic to the virtual machine. Allowed values: `WholeIP` and `PortList` | `PortList`   |
| `externalPorts`           | Specify ports to forward from outside the cluster                                                          | `[]`         |
| `running`                 | Determines if the virtual machine should be running                                                        | `true`       |
| `instanceType`            | Virtual Machine instance type                                                                              | `u1.medium`  |
| `instanceProfile`         | Virtual Machine preferences profile                                                                        | `ubuntu`     |
| `systemDisk.image`        | The base image for the virtual machine. Allowed values: `ubuntu`, `cirros`, `alpine`, `fedora` and `talos` | `ubuntu`     |
| `systemDisk.storage`      | The size of the disk allocated for the virtual machine                                                     | `5Gi`        |
| `systemDisk.storageClass` | StorageClass used to store the data                                                                        | `replicated` |
| `gpus`                    | List of GPUs to attach                                                                                     | `[]`         |
| `resources.cpu`           | The number of CPU cores allocated to the virtual machine                                                   | `""`         |
| `resources.memory`        | The amount of memory allocated to the virtual machine                                                      | `""`         |
| `sshKeys`                 | List of SSH public keys for authentication. Can be a single key or a list of keys.                         | `[]`         |
| `cloudInit`               | cloud-init user data config. See cloud-init documentation for more details.                                | `""`         |
| `cloudInitSeed`           | A seed string to generate an SMBIOS UUID for the VM.                                                       | `""`         |

## 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](./DEVELOPMENT.md).

## Resources

The following instancetype resources are provided by Cozystack:

Name | vCPUs | Memory
-----|-------|-------
cx1.2xlarge  |  8  |  16Gi
cx1.4xlarge  |  16  |  32Gi
cx1.8xlarge  |  32  |  64Gi
cx1.large  |  2  |  4Gi
cx1.medium  |  1  |  2Gi
cx1.xlarge  |  4  |  8Gi
gn1.2xlarge  |  8  |  32Gi
gn1.4xlarge  |  16  |  64Gi
gn1.8xlarge  |  32  |  128Gi
gn1.xlarge  |  4  |  16Gi
m1.2xlarge  |  8  |  64Gi
m1.4xlarge  |  16  |  128Gi
m1.8xlarge  |  32  |  256Gi
m1.large  |  2  |  16Gi
m1.xlarge  |  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.7 | CentOS 7
centos.7.desktop | CentOS 7
centos.stream10 | CentOS Stream 10
centos.stream10.desktop | CentOS Stream 10
centos.stream8 | CentOS Stream 8
centos.stream8.desktop | CentOS Stream 8
centos.stream8.dpdk | CentOS Stream 8
centos.stream9 | CentOS Stream 9
centos.stream9.desktop | CentOS Stream 9
centos.stream9.dpdk | CentOS Stream 9
cirros | Cirros
fedora | Fedora (amd64)
fedora.arm64 | Fedora (arm64)
opensuse.leap | OpenSUSE Leap
opensuse.tumbleweed | OpenSUSE Tumbleweed
rhel.10 | Red Hat Enterprise Linux 10 Beta (amd64)
rhel.10.arm64 | Red Hat Enterprise Linux 10 Beta (arm64)
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)
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.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)
