The Proxmox Virtual Environment platform keeps gaining weight in the virtualization landscape. Austrian company Proxmox Server Solutions has announced the release of Proxmox VE 9.1, the first major point update in the 9.x branch and an important step for organisations looking for a modern, open alternative to proprietary virtualization stacks.
The new version arrives only a few months after Proxmox VE 9.0 and focuses on three very specific fronts: containers, virtual-machine security and software-defined networking. All of this sits on a fully updated technical base: Debian 13.2 “Trixie” and the Linux 6.17.2 kernel, together with QEMU 10.1, LXC 6.0.5, ZFS 2.3.4 and Ceph Squid 19.2.3, among other cutting-edge components.
Beyond virtual machines: LXC from OCI images
One of the most eye-catching changes in Proxmox VE 9.1 is the ability to create LXC containers directly from OCI (Open Container Initiative) images. Until now, administrators depended on Proxmox-specific templates or manually adapted images. With the new support, they can reuse standard images from public or private container registries and turn them into LXC containers almost immediately.
In practice, this means that a development team already building OCI images in its CI/CD pipeline can reuse exactly the same artifacts to deploy applications in Proxmox VE without intermediate steps. The platform can create both full system containers and very lean application containers, which is especially interesting for microservices, APIs or databases that need fast startup and low resource consumption.
This convergence between the traditional container world and KVM virtualization brings Proxmox VE closer to the “software-defined data center” model many companies are pursuing: a single control plane for virtual machines, containers and software-defined storage.
Stronger security: vTPM state in qcow2 and more flexible backups
Security for guest systems is another pillar of Proxmox VE 9.1. The new version introduces the option to store the state of virtual Trusted Platform Modules (vTPMs) inside qcow2 disk images. This seemingly small change has a very real impact on daily operations.
Up to now, machines using vTPM—for example, modern Windows installations that require TPM 2.0—could impose limitations when creating consistent snapshots and backups. By embedding the vTPM state into the qcow2 disk, Proxmox VE makes it possible to take full snapshots even on shared storage such as NFS or CIFS and in LVM setups with volume chains. The result is simpler management of sensitive workloads, from hardened Windows servers to VDI environments.
For organisations migrating from VMware and needing to maintain or improve compliance requirements, this kind of technical detail often makes the difference between a proof-of-concept and a stable production platform.
Nested virtualization under the microscope: new vCPU flag
Nested virtualization has become a common requirement in lab environments, training platforms or multi-tenant infrastructures where customers run their own hypervisors. Proxmox VE 9.1 introduces a new vCPU flag that allows virtualization extensions to be enabled for each virtual machine in a very granular way.
Instead of exposing the full instruction set of the host CPU to the guest—a functional but less controllable practice—administrators can now activate only what is needed for specific scenarios: nested hypervisors, test environments using KVM or Hyper-V, or Windows systems relying on Virtualization-based Security (VBS). The result is a finer balance between performance, compatibility and attack surface.
More visibility for software-defined networking
Proxmox VE has been investing in its own SDN layer for several versions. What changes in 9.1 is not the concept but the visibility: the web interface now provides a much richer view of the virtual network state across the whole cluster.
Admins can see which guests are connected to each bridge or VNet, inspect IP addresses and MACs learned in EVPN zones, and review routes and neighbours for each fabric, as well as information on IP-VRFs and MAC-VRFs. Previously, this level of detail required dropping into the command line and external monitoring tools.
In environments with dozens or hundreds of machines, this integrated observability is key for troubleshooting connectivity issues, analysing bottlenecks or validating complex networking changes without jumping between consoles.
Updated underpinnings: Debian 13 and kernel 6.17
From a platform perspective, Proxmox VE 9.1 consolidates the move to Debian 13 “Trixie” that arrived with version 9.0. Release 9.1 is based on Debian 13.2 and ships Linux 6.17.2 as the default kernel, newer than the 6.14.8 used in Proxmox VE 9.0.
The update does not stop there. QEMU, the KVM virtualization engine, moves to the 10.1 series; LXC is updated to 6.0.5; ZFS to 2.3.4; and Ceph Squid to 19.2.3 for those using distributed storage. These newer versions bring performance improvements, bug fixes and new features, particularly in networking, snapshots and replication.
A mature project with more than 1.6 million hosts
Although Proxmox VE remains a free-software project (AGPLv3) that can be installed at no cost on top of Debian, the surrounding ecosystem is increasingly enterprise-oriented. According to the company, the project now runs on more than 1.6 million hosts worldwide, with over 225,000 active users in the community forums. Tens of thousands of business customers pay for support subscriptions to access the Enterprise repository and certified technical assistance.
The model is simple: anyone can download the installation ISO and deploy Proxmox VE on bare metal or on top of an existing Debian 13 system. For production, the company recommends subscribing from 115 euros per CPU and year, which enables updates from the stable repository and access to support. This hybrid approach—strong community plus commercial support—has become one of Proxmox’s main arguments against proprietary alternatives.
Quick comparison: Proxmox VE 8.4, 9.0 and 9.1
For organisations still running 8.x clusters or planning a move from 9.0, it helps to put key differences in context:
| Key feature | Proxmox VE 8.4 | Proxmox VE 9.0 | Proxmox VE 9.1 |
|---|---|---|---|
| Base system | Debian 12.10 “Bookworm” | Debian 13.0 “Trixie” | Debian 13.2 “Trixie” |
| Default kernel | Linux 6.8 (optional 6.14) | Linux 6.14.8 | Linux 6.17.2 |
| QEMU version | 9.2 | 10.0 (10.0.x series) | 10.1 (10.1.x series) |
| LXC version | 6.0.0 | 6.0.4 | 6.0.5 |
| ZFS version | 2.2.7 | 2.3.3 | 2.3.4 |
| Integrated Ceph version | Ceph Squid 19.2.1 | Ceph Squid 19.2.x | Ceph Squid 19.2.3 |
| Estimated Proxmox support window | Security fixes until Aug 2026 | To be announced | To be announced |
| Key new features | Import wizard for VMs/CT, backup and Ceph improvements | Jump to Debian 13, redesigned installer, Ceph Squid | OCI-based LXC containers, vTPM state in qcow2, richer SDN views |
Exact version numbers may slightly change as minor updates are applied, but the table offers a clear picture of how the product has evolved within a year: from Debian 12 to Debian 13, modernised kernel and core components, and new capabilities focused on observability and security.
Upgrades and lifecycle
Operationally, Proxmox VE 9.1 can be installed from scratch using the official ISO or layered on top of a clean Debian 13 system. For existing Proxmox VE 8.4 deployments, the recommended path is to follow the official upgrade guide: first bring the cluster to the latest 8.x point release and then move to 9.x via APT, ideally using the Enterprise repository in critical environments.
Clusters running Ceph Reef must migrate to Squid before upgrading the Proxmox VE version, in a two-step procedure documented in the official wiki. This kind of constraint reinforces the idea that, even though Proxmox VE keeps a “friendly” image, major upgrades should be planned as proper infrastructure projects, with testing and maintenance windows.
One more step in the open alternative to VMware
The arrival of Proxmox VE 9.1 coincides with deep shifts in the virtualization market, driven by VMware’s strategic changes after its acquisition by Broadcom and by the growing interest of companies seeking to reduce dependence on single vendors.
In this context, Proxmox VE positions itself as one of the leading options for those who prefer Linux-based, open technologies: KVM, LXC, Ceph, ZFS and a unified web interface to manage the whole stack. Version 9.1 does not introduce radical revolutions, but it does refine the product where it mattered most: standards-compliant containers via OCI, better handling of vTPM-protected machines, fine-grained nested virtualization and a more transparent SDN layer.
For many organisations, that bundle of improvements may be the final push needed to plan a gradual migration away from proprietary platforms and towards a more flexible, vendor-agnostic data center.
Frequently asked questions about Proxmox VE 9.1
Is it worth upgrading from Proxmox VE 8.4 to 9.1 right now?
For labs and non-production environments, the answer is largely yes: you can test Debian 13, the new kernel and features like OCI-based containers and improved SDN visibility. In production, the decision should factor in storage dependencies (especially Ceph) and your own change-management calendar, bearing in mind that Proxmox VE 8.4 will still receive security updates until August 2026.
What practical benefits do LXC containers from OCI images bring?
The main benefit is tight integration with existing container pipelines. Instead of maintaining Proxmox-specific templates, teams can reuse exactly the same images they deploy elsewhere, reducing errors, maintenance work and the risk of discrepancies between test and production.
How does storing vTPM state in qcow2 affect backups?
By embedding the vTPM state inside a qcow2 disk, Proxmox VE 9.1 can create consistent snapshots and backups of machines that depend on TPM, such as many modern Windows systems. This simplifies disaster recovery and removes manual workarounds or storage-specific limitations.
Is Proxmox VE 9.1 a realistic replacement for VMware vSphere in enterprises?
Every environment is different, but from a technical standpoint Proxmox VE 9.1 covers most common scenarios: high availability, integrated backup, software-defined storage, SDN, containers and commercial support. For organisations aiming to cut license costs and avoid vendor lock-in, Proxmox VE 9.1 stands out as one of the most mature open alternatives on the market.
