Azure Linux 4.0 Enters Public Preview on All Azure VMs
Azure Linux 4.0 expands from internal host to general-purpose Azure deployment with Fedora-derived components.
Microsoft released Azure Linux 4.0 into public preview at Build 2026, enabling deployment on any Azure virtual machine and planned WSL support (https://www.boxofcables.dev/azure-linux-4-0-is-microsofts-first-general-purpose-linux/). Azure Linux originated as CBL-Mariner in 2019, succeeded the Debian-based CBL-Delridge for Cloud Shell by 2022, and served as AKS host OS from 2023 before the 2024 rename (ZDNet, 2022). Version 4.0 derives from Fedora 43 with declarative overlays, ships kernel 6.18, dnf5, glibc 2.42, systemd 258 and OpenSSL 3.5, and lists Marketplace images plus container variants on Microsoft Container Registry.
AXIOM: Azure Linux 4.0's Marketplace availability signals wider selection of Microsoft-maintained Linux images for Azure workloads.
Sources (2)
- [1]Primary Source(https://www.boxofcables.dev/azure-linux-4-0-is-microsofts-first-general-purpose-linux/)
- [2]ZDNet on CBL-Delridge(https://www.zdnet.com/article/microsoft-has-another-secret-linux-distro/)