Canonical has released the beta version of “snappy” Ubuntu Core, a lightweight and cloud-optimised version of Ubuntu Linux, on Microsoft Azure, Google Compute Engine and Amazon Web Services.
Ubuntu Core is a new rendition of Ubuntu that has been designed as a minimal, secure and reliably updatable operating system (OS) base image for hosting cloud applications and container-oriented deployments using technologies like Docker and the emerging orchestration platforms.
Snappy Ubuntu Core is provided as a minimal server image that only features the necessary libraries to install additional frameworks and packages required by developers, for example, a container system such as Panamax. The installed components are run securely in their own sandboxed “AppArmor” environments, which is Canonical’s Linux Security Module (LSM) kernel enhancement to confine programs to a limited set of resources using a Mandatory Access Control (MAC) system.
The Ubuntu Insights blog states that safe and reliable updates for both the snappy Ubuntu Core OS and associated applications are provided by using “transactional, image-based delta updates”. The OS and application files are stored separately as read-only images, which are updated transactionally with small-sized change deltas. A backup of all associated data is also captured before an update, and the image and data can be rolled back if a problem occurs. This ensures that the system is never in an incomplete state.
Mark Shuttleworth, founder of Canonical and Ubuntu, states that snappy Ubuntu Core originated out of work on Canonical’s mobile phone OS, which shared similar requirements to container-based Cloud hosting platforms, such as a highly secure read-only OS and updates that never break the device or associated applications. Shuttleworth also states that fixes to the Ubuntu OS and associated packages will also be published to Ubuntu Core.
The Ubuntu Insights blog states that motivation for the “snappy” moniker is primarily based on the speed and reliability of deployment. “The snappy approach is faster, more reliable, and lets us provide stronger security guarantees for apps and users - that’s why we call them ‘snappy’ applications”.
Snappy Ubuntu Core provides similar functionality to CoreOS, Inc’s CoreOS and Red Hat's Project Atomic, and the primary focus is provide developers and system administrators with a minimal Linux server that supports containers or container orchestration frameworks as a foundational basis for building Cloud applications.
Shuttleworth states that the primary differences between Ubuntu Core and other similar projects is that Ubuntu Core will be more lightweight, extensible and secure. For example, the base Ubuntu Core distribution will not include a default cluster management framework, such as Fleet provided by CoreOS or Kubernetes provided by Project Atomic. Security of frameworks and packages is assured within Ubuntu Core by providing a single repository of components which are digitally fingerprinted.
Snappy Ubuntu Core is available on Microsoft’s Azure cloud platform, Google Compute Engine (GCE) and Amazon Web Service’s EC2 IaaS platform, and can be installed locally using KVM.
Detailed instructions for launching a snappy Ubuntu Core instance on any of the platforms mentioned above can be found on the Ubuntu Insights website.
