Virtualization on Cozystack

Running Cozystack on Three 8 GB Raspberry Pi 5 Boards

Thu, 12 Nov 2026 00:00:00 +0000

Three Raspberry Pi 5 boards on a desk, and on them a cluster that runs containers and virtual machines, with multi-tenancy, managed databases and everything else Cozystack provides.

Why bother? Cozystack is usually installed on a rack of servers in a data center, so just trying the platform out means renting hardware or spinning up VMs in a cloud. Three Raspberry Pis cost about as much as a dinner out, fit in a backpack and run from a wall socket. You can learn on them, demo Cozystack at a conference, debug your own automation or keep a small cloud at home. And I was curious how far the platform can be squeezed and what breaks first.

Cozystack 1.7: ARM, Proxmox as a KubeVirt Alternative, and Automated VMware Migrations

Wed, 11 Nov 2026 00:00:00 +0000

Cozystack v1.7.0 is now available. The release was published on October 29, 2026.

This release removes several of the usual reasons teams give for putting off a move to the platform. It is aimed at those who already run Proxmox VE and want to keep it, those leaving VMware and wondering how to bring their virtual machines along, and those who cannot expose a database without encryption or back up anything other than PostgreSQL.

A community catalog brings Niklaus Wirth's Oberon machine to Cozystack as an installable app

Wed, 30 Sep 2026 00:00:00 +0000

A community contributor has published a pluggable Cozystack catalog that does something Cozystack was never built to do: it runs Niklaus Wirth’s RISC5 processor — the tiny teaching CPU Wirth designed for the 2013 edition of Project Oberon — as an ordinary cloud VM. From a tenant’s point of view, the 1980s Oberon workstation installs like any other app in the catalog: a short form, or a single OberonVM resource, and the machine boots on a VNC console next to the PostgreSQL and Kubernetes instances. The whole thing is open source under Apache 2.0; the QEMU processor model, like QEMU itself, is under the GPL.

Security Advisory — CVE-2026-53359 ("Januscape"): KVM Guest-to-Host Escape

Wed, 08 Jul 2026 00:00:00 +0000

Severity: High for clusters running virtualization. Status: No fixed Talos release yet — mitigation required now.

What happened

On 2026-07-06 a Linux kernel vulnerability, CVE-2026-53359 (“Januscape”), was publicly disclosed together with a working exploit. It is a use-after-free in the KVM/x86 shadow MMU that lets a guest VM break out to its host (the cluster node) or crash the node’s kernel. It affects both Intel and AMD CPUs and has been latent in the kernel since 2010.

Cozystack 1.3: Storage-Aware Scheduling, LINSTOR GUI, and VM Default Images

Thu, 23 Apr 2026 00:00:00 +0000

Cozystack 1.3: Storage-Aware Scheduling, LINSTOR GUI, and VM Default Images

Cozystack v1.3.0 is now available. The release also rolls up every fix shipped in the v1.2.1 → v1.2.4 patch line.

This cycle pushes the platform forward in five clear directions: smarter storage placement, a managed UI for LINSTOR, a built-in catalog of VM base images, deeper application-level observability, and a complete cross-namespace VM backup-restore experience.

Main highlights

Storage-aware scheduling via the LINSTOR extender

The cozystack-scheduler now consults a LINSTOR scheduler extender when placing pods that declare both a SchedulingClass and LINSTOR-backed PVCs. Pods are preferentially scheduled to nodes where their volume replicas already live, cutting cross-node replication traffic and lowering I/O latency for storage-heavy workloads — databases, object stores, VMs.