Canonical has announced the public preview of Ubuntu Core 26 (released back in May, based on Ubuntu 26.04 LTS) images for Amazon Web Services, Microsoft Azure, and Google Cloud, extending its immutable Linux distro designed for embedded and IoT devices to public cloud environments.
With this new offering, Canonical is targeting virtual appliances, managed services, and specialized workloads where predictable configurations and controlled updates are more important than unrestricted system customization.
In Ubuntu Core, updates are transactional, allowing the system to recover from failed upgrades instead of being left partially updated. Security updates are handled automatically, with the kernel, base system, and applications maintained as independently updated snaps.
Moreover, applications run under strict confinement, limiting access to system resources through explicitly defined interfaces, and the underlying operating system is immutable, reducing unintended modifications to system components.
Bringing all this to public clouds required Canonical to make multiple technical changes. For example, AWS, Azure, and Google Cloud use optimized Linux kernels that Canonical traditionally distributes as DEB packages. These kernels are now packaged as cloud-specific snaps to work within Ubuntu Core’s architecture.
Additionally, cloud guest agents have been converted into snaps, giving each its own update lifecycle and security policy. Under strict confinement, the agents must explicitly declare which system resources and interfaces they need.
Canonical emphasizes that Ubuntu Core is not a replacement for Ubuntu Server. The latter remains the appropriate option for general-purpose servers requiring traditional package management, interactive administration, and extensive host customization. Ubuntu Core targets systems built around a predefined set of components that can be maintained and updated consistently.
The preview images are available through the marketplaces of AWS, Azure, and Google Cloud. Canonical also provides instructions for launching instances, installing additional snaps, and creating custom Ubuntu Core images.
For additional details, see the announcement.
