Get Cloud Images

Overview

Pre-built cloud images are official distribution releases packaged for virtual machine deployment. Each image includes cloud-init for first-boot customization, SSH server access, and storage drivers optimized for virtual environments. Use these images as the starting point for new instances rather than installing an operating system from scratch.

Prerequisites

An active Polystack account with appropriate permissions
Access to the Polystack Dashboard or CLI configured with credentials
API credentials sourced (source openrc.sh)

Start with CirrOS for initial environment testing. It is a minimal test image that launches in seconds and consumes almost no resources.

Available Images

All images listed below require cloud-init to function correctly in Polystack. Images without cloud-init will not receive SSH keys, hostname assignments, or network configuration on launch.

Distribution	Download URL	Format	Default User
Ubuntu 24.04 LTS	cloud-images.ubuntu.com	QCOW2	`ubuntu`
Ubuntu 22.04 LTS	cloud-images.ubuntu.com	QCOW2	`ubuntu`
CentOS Stream 9	cloud.centos.org	QCOW2	`cloud-user`
AlmaLinux 9	repo.almalinux.org	QCOW2	`almalinux`
Rocky Linux 9	dl.rockylinux.org	QCOW2	`rocky`
Debian 12	cloud.debian.org	QCOW2	`debian`
Fedora 41	fedoraproject.org	QCOW2	`fedora`
CirrOS 0.6.2	download.cirros-cloud.net	QCOW2	`cirros` / pass: `gocubsgo`
Windows Server and Windows Desktop	Prepare from licensed installation media or evaluation media	VHD / QCOW2	`Administrator`

Polystack supports Windows Server and Windows desktop images when they are prepared for virtualization with Cloudbase-Init and the required VirtIO drivers. Common versions include Windows Server 2016, 2019, 2022, and 2025, plus Windows 10 and Windows 11 desktop images. Use your organization’s licensed media or approved evaluation media, convert the disk to the required image format, and upload it as a Windows image.

Windows Server evaluation images expire after 180 days. For production use, supply a licensed Windows image prepared with Cloudbase-Init installed.

Download and Upload an Image

Dashboard
CLI

Navigate to Images

Navigate to Compute > Images. Click Create Image.

Configure the image record

Field	Recommended Value
Name	`ubuntu-24.04-lts`
Upload Type	File URL (for web download) or Upload File (for local upload)
File URL	Paste the download URL from the table above
Disk Format	`QCOW2`
OS	Select the matching distribution (e.g., Ubuntu)
OS Version	`24.04`
OS Admin	`root` (Linux) or `Administrator` (Windows)
Min System Disk (GiB)	`10` for most Linux images; `40` for Windows
Min Memory (GiB)	`1` for Linux; `2` for Windows

See Upload an Image for the complete field reference.

Create the image

Click Confirm. The image enters Saving status while the file is fetched and stored. Large images may take several minutes.

The status transitions to Active when storage is complete. The image is available immediately for launching instances.

Authenticate

Source your credentials file to authenticate with the Polystack platform:

Load credentials

source openrc.sh

Your administrator provides the RC (credentials) file for your project. See CLI Setup for configuration details.

Download the image locally

Download Ubuntu 24.04 LTS cloud image

curl -L -o ubuntu-24.04-lts.img \
  https://cloud-images.ubuntu.com/noble/current/noble-server-cloudimg-amd64.img

Verify the download completed and matches the published checksum:

Verify checksum (SHA256)

sha256sum ubuntu-24.04-lts.img

Upload to the image service

Upload image with metadata

openstack image create \
  --disk-format qcow2 \
  --container-format bare \
  --file ubuntu-24.04-lts.img \
  --min-disk 10 \
  --min-ram 512 \
  --property os_type=linux \
  --property os_distro=ubuntu \
  --property os_version=24.04 \
  ubuntu-24.04-lts

Note the image id from the output for verification.

Verify the image is active

Check image status

openstack image show ubuntu-24.04-lts -c status -c size -c disk_format

status shows active — the image is ready for use with instances.

Validation

Confirm the uploaded image is registered and ready before launching instances.

Dashboard
CLI

Navigate to Compute > Images. Locate the image by name and verify:

Status: Active (green indicator)
Format: Matches the selected disk format
Size: Matches the expected download size

Image shows Active status and is selectable when launching a new instance.

List images and filter by name

openstack image list --name ubuntu-24.04-lts -c Name -c Status -c "Disk Format"

Expected output:

Expected output

+------------------+--------+-------------+
| Name             | Status | Disk Format |
+------------------+--------+-------------+
| ubuntu-24.04-lts | active | qcow2       |
+------------------+--------+-------------+

Status active confirms the image is stored and ready for compute use.

Next Steps

Image Requirements

Understand what makes an image compatible with Polystack Compute.

Upload an Image

Upload images from local files or import via web URL.

Convert Formats

Convert VMDK, VHD, or RAW images to QCOW2 before uploading.

Image Properties

Set OS metadata, hardware requirements, and scheduler hints.

Core Services

Other Services

Overview

Available Images

Download and Upload an Image

Navigate to Images

Configure the image record

Create the image

Authenticate

Download the image locally

Upload to the image service

Verify the image is active

Validation

Next Steps

Image Requirements

Upload an Image

Convert Formats

Image Properties

​Overview

​Available Images

​Download and Upload an Image

Navigate to Images

Configure the image record

Create the image

Authenticate

Download the image locally

Upload to the image service

Verify the image is active

​Validation

​Next Steps

Image Requirements

Upload an Image

Convert Formats

Image Properties

Overview

Available Images

Download and Upload an Image

Validation

Next Steps