After using Azure Linux internally for two years and running it in public preview since October 2022, Microsoft this week finally made its distribution available to everyone.
Azure Linux is an open-source container host operating system for Azure Kubernetes Service (AKS from Azure Kubernetes Service) that is optimized for Azure and aims to make it easier for developers to use Microsoft tools for deployment and management of containers.

Azure Linux is designed to be deployed in the cloud and run multiple containers together.
The Azure Linux distribution comes from the CBL-Mariner project by Microsoft, where CBL stands for Common Base Linux. Microsoft started CBL-Mariner because it needed an internal Linux distribution and a consistent one platform for the thousands of workloads engineers were running on Azure, according to Jim Perrin, principal program manager for Microsoft Azure Linux.
Microsoft's custom open source distribution “allows us to have a very defined, very thoughtful focus on Azure and tune the elements of the distribution to be exactly what we need to support a central computer for containers and try to keep dependencies, external packages, to a minimum,” Perrin said during a Q&A session at Build 2023, where Redmond announced the general availability of Azure Linux.
This means that Azure Linux's primary role is as a container host for AKS. It is optimized for Microsoft's Windows Hyper-V hypervisor and runs in a virtual machine (VM), supporting both x86 and Arm.
The lightweight nature of distribution is a key point, Perrin said. The small footprint includes a 400MB kernel image and 300 packages, which Microsoft said works very well for both performance and security.
Safety was the focus, Perrin said in a publication, noting that all updates to the operating system are run through Azure validation tests and that the test suite is constantly updated.
“Επιπλέον, δεδομένου ότι υπάρχουν πολύ λιγότερα πακέτα στον κεντρικό υπολογιστή container, ο όγκος των απαιτούμενων ενημερώσεων ασφαλείας είναι μικρότερος και αυτά τα ζητήματα επιδιορθώνονται επίσης αμέσως. Παρακολουθούμε στενά και διαχειριζόμαστε πλήρως την αλυσίδα εφοδιασμού software, η οποία επιτρέπει μεγαλύτερη διασφάλιση ποιότητας και ανθεκτικότητας από άκρη σε άκρη.”
Also at Build, Microsoft announced that Kubernetes Apps, a collection of third-party open source applications for the AKS platform, is available in the Azure Marketplace.
Οι εφαρμογές Kubernetes, οι οποίες τέθηκαν σε δημόσια προεπισκόπηση τον Οκτώβριο του 2022, επιτρέπουν την ανάπτυξη με ένα click, την αυτοματοποίηση CI/CD, την αυτοματοποιημένη διαχείριση κύκλου ζωής και την υποστήριξη.
Available apps are tested and certified by Microsoft and scanned for vulnerable points, a necessary step at a time when the number of attacks through the supply chain continues to increase.
