Review of the Dutch Proxmox Day 2025

On September 25, 2025, we attended the Dutch Proxmox Day 2025 in Ede (Netherlands) – and I must say: the event was a complete success. Organized by Tuxis B.V. at the Hotel Belmont in the Veluwe region, the day offered an excellent mix of expert presentations and valuable exchange.

Thanks to the Hosts

A heartfelt thank you to the Tuxis team: For the invitation as a speaker, for the trust placed in us, and for the perfect organization. Yes — this blog article is coming a bit late, but as they say: better late than never.

My Perspective as a Speaker

As a speaker, I had the pleasure of being part of an exciting program. At the same time, I was a participant: both at the same time – that’s what makes such days special. I would like to highlight a few presentations:

• Aaron Lauterer (Linux Software Developer at Proxmox Server Solutions) – “Let’s get technical with a Proxmox developer”: A look at upcoming features of Proxmox VE. The upcoming integration of OCI containers (aka Docker) is particularly exciting.
• Rob Turk (Senior Presales Systems Engineer at Veeam) – “Save the data”: Clearly shows that Proxmox has now arrived in the enterprise world.
• Mark Schouten (CTO at Tuxis) – “Cool stuff you can do with Proxmox”: Proxmox Backup Server in interaction with ZFS, how to make the whole thing more performant and what unexpected problems with SCSI and Western Digital have occurred, Mark Schouten told us about it
• Alexander Wirt – “Balancing workloads in Proxmox”: My own contribution with a focus on the project ProxLB of my esteemed colleague Florian Hoberg, which distributes virtual machines evenly across nodes, again shows the advantages and OSS and open interfaces. These make it easy to add missing functionality and thus compete with the industry giants.
• Robbe Van Herck (Support & Maintenance Engineer at International Polar Foundation) – “Proxmox on Antarctica”: Proxmox in extreme use – at the other end of the world and very far from everyday data center life. Robbe was able to show well that Proxmox also works in the most remote corners of the earth, the other challenges are more exciting here – such as hardware that is overwhelmed by the low temperatures.
• Han Wessels (Operations System Engineer at ESA) – “Challenged to run Proxmox out of this world”: Why Proxmox can also be operated on the ISS or in space – technology meets vision. Han vividly described the challenges that arise, such as the vibration during the launch of the carrier rocket or the radiation that significantly shortens the lifespan of storage.

I was able to take away many impulses – both technically and ideally. And I had good conversations that will certainly pay off further.

Networking & Exchange

The informal part was just as valuable as the program: during the breaks, at lunch or at the get-together in the afternoon, we made new contacts, gained interesting insights and met old acquaintances. It is precisely these moments that make a conference come alive.

Outlook

We are already looking forward to next year. When the Tuxis team calls again, we will be happy to be there again. Many thanks again to all those involved, all speakers and all participants – see you again. In between, this December there will be the first Open Source Virtualization Gathering at our company.

NetApp Storage and NVMe-oF for Breakthrough Performance in Proxmox Virtualization Environments

What is NVMe-oF

NVMe over Fabrics (NVMe-oF) is a cutting-edge protocol that has been developed to bring the impressive performance and low-latency characteristics of NVMe storage devices over network fabrics. This innovation is particularly transformative for data centers, as it facilitates the separation of storage and compute resources, granting administrators the ability to deploy these resources more flexibly and with greater scalability which makes it perfectly fine for virtualization workloads.

NVMe-oF is versatile in its support for multiple transport layers where it can operate over Fibre Channel (FC), Ethernet with the TCP/IP protocol with RDMA capabilities through RoCE or iWARP, and even utilize InfiniBand, each offering unique performance features tailored to different deployment needs.

NVMe-oF via TCP

When NVMe-oF is deployed over Ethernet with TCP, it brings the benefits of NVMe storage to the broadest possible range of environments without the need for specialized network infrastructure like Fibre Channel or InfiniBand. This brings access to high-performance storage by utilizing the common and familiar TCP stack, significantly reducing complexity and cost. The adoption of NVMe-oF with TCP is further facilitated by the widespread availability of Ethernet and expertise, making it a compelling choice for organizations looking to upgrade their storage networks without a complete overhaul.

The protocol’s efficiency is well maintained even over TCP, allowing NVMe commands to be passed with minimal overhead, thus keeping latency at bay, which is critical for latency-sensitive applications like virtualized data servers.

Configuring NetApp Storage

General

The guide presumes that users have already established the foundational storage setup, including the configuration of Storage Virtual Machines (SVMs). It highlights that the administration of these systems is relatively straightforward, thanks to the intuitive web interface provided by NetApp storage systems. Users can expect a user-friendly experience when managing their storage solutions, as the web interface is designed to simplify complex tasks. This also includes the whole setup for NVMe-oF storage, which requires to enable NVMe in general on the SVM, setting up the NVMe namespace and the NVMe subsystem.

Note: All changes can of course also be performed in an automated way by orchestrating the OnTap API.

Enable NVMe on SVM

To enable NVMe at the SVM level on a NetApp storage system, this can typically be done by following these summarized steps, which can be accessed through the system’s web interface. Simply  navigate to the Storage menu, then to Storage VMs, and finally selecting the specific SVM name you wish to configure:

1. Configure NVMe Protocol: Within the SVM settings, look for a section or tab related to protocols. Locate the NVMe option and enable it. This might involve checking a box or switching a toggle to the ‘on’ position.
2. Save and Apply Changes: After enabling NVMe, ensure to save the changes. There might be additional prompts or steps to confirm the changes, depending on the specific NetApp system and its version.

Remember to check for any prerequisites or additional configuration settings that might be required for NVMe operation, such as network settings, licensing, or compatible hardware checks. The exact steps may vary slightly depending on the version of ONTAP or the specific NetApp model you are using. Always refer to the latest official NetApp documentation or support resources for the most accurate guidance.

Creating the NVMe Subsystem

Afterwards, a new NVMe subsystem can be created on the NetApp storage system. This can be done by selecting the Hosts section, and choosing NVMe Subsystem to start the process of adding a new subsystem. A new wizard opens up which requires additional information regarding the newly to be created subsystem:

Name: <An identifier of the NVMe subsystem>
Storage VM: <The previously adjusted SVM>
Host Operating System: Linux (important for the block size)
Host NQN: <NQN of the Proxmox VE node>

It’s essential to ensure that all information, especially the Hosts NQN, is correctly entered to avoid connectivity issues. Additionally, consult the official NetApp documentation for any version-specific instructions or additional configuration steps that may be required.

Creating the NVMe Namespace

As a last step the NVMe namespace must be created. To add an NVMe namespace on a NetApp storage system, you would begin by logging into the web interface and navigating to the Storage section, followed by selecting NVMe Namespaces. In this area, you initiate the process of creating a new namespace. You will be prompted to provide specific details for the namespace, such as its name, size, and the associated SVM that will manage it.

Note: Also take an important note about the Performance Service Level which might be switched to a custom profile to avoid any limitations.

Once you have entered all the necessary information, you will typically proceed to choose the performance characteristics, like the service level or tiering policy, depending on your performance needs and the capabilities of your NetApp system.

After configuring these settings, you need to review your choices and save the new namespace configuration to make it available for use. It is important to ensure that the namespace is properly configured to match the requirements of your environment for optimal performance and compatibility. Always check for any additional steps or prerequisites by consulting the NetApp documentation relevant to your ONTAP version or storage model.

The configuration on the storage part is now complete. The next steps will be performed on the Proxmox VE node(s).

Configuring Proxmox Node

General

After configuring the NetApp storage appliance, all Proxmox VE nodes within the cluster must be configured to use and access the NVMe-oF storage. Unfortunately, Proxmox VE does not support this type of storage out of the box. Therefore, this cannot be easily configured by the Proxmox web interface. Luckily, Proxmox VE is based on Debian Linux from where all needed dependencies and configurations can be obtained but it requires us to do everything on the command line (CLI). Depending on the amount of nodes within the cluster, further config management tools like Ansible may boost up the initial setup process and make it repeatable for new potential nodes in the future. We may also assist you by setting up custom config management environments fitting your needs.

In general, this process consists of:

• Installing needed packages.
• Enabling the Kernel modules.
• Discovery of the storage.
• Connecting with the storage.
• Creating a LVM Volume Group.
• Assigning the storage in the Proxmox web interface.

The next steps in this blog post will cover the process in detail and guide you through the needed steps on the Proxmox VE nodes which must be done on the command line.

Installing Needed Packages

Using and accessing NVMe-oF requires the related user land tools (nvme-cli) to be present on the Proxmox VE node. Debian Linux already provides those tools within the Debian repository. As a result, the overall installation process is very easy. The package can simply be installed by the following command:

apt-get install nvme-cli

This package also already provides the required Kernel module which can simply be loaded by running:

modprobe nvme_tcp

Afterwards, the module should be added to be loaded at boot time:

echo "nvme_tcp" > /etc/modules-load.d/20-nvme_tcp.conf

After these steps, a connection with the storage can be initialized.

Connecting With the Storage

Interacting with the NetApp storage and its NVMe-oF functionality is a multi-step process and requires us to exchange the NVMe Qualified Name (NQN) address of each Proxmox VE node accessing the NVMe storage. The NQN address of a Proxmox VE node can be obtained by running the command:

cat /etc/nvme/hostnqn

Add the host NQN address on your NetApp export to allow the nodes accessing it. An example output is given in the screenshot.

Discovery & Connecting

In the next step, the NVMe’s will be discovered and connected to the Proxmox VE node. The discovery and connect process is simply done by running the following commands:

nvme discover -t tcp -a 192.168.164.100 -s 4420
nvme connect -t tcp -n na01-nqn01 -a 192.168.164.100 -s 4420

To make this configuration persistent to system reboots, the commands will also be added to the nvme discovery file. The nvmf-autoconnect systemd unit file ensures to load this. Therefore, this systemd unit file must also be enabled.

echo "discover -t tcp -a 192.168.164.100 -s 4420" >> etc/nvme/discovery.conf
systemctl enable nvmf-autoconnect.service

Volume Group

The last steps will partially be done on the command line and on the Proxmox web interface to add the new storage to the cluster.

Important:
This steps must only be done on a single Proxmox VE host node and not on all ones. The integration happens on cluster level and implies all Proxmox VE nodes once this has been done.

The last command on the command line results in creating a new LVM Volume Group (VG) on the new NVMe device which can simply be done by executing the command:

vgcreate shared_nvme01 /dev/nvme0n1

The newly created LVM Volume Group (VG) can be validated by running the command:

vgdisplay shared_nvme01

An output like in the given screenshot should be returned, including all further details of this VG. After validating the information, all tasks are completed on the command line.

To finally use this LVM Volume Group on all Proxmox VE nodes within the cluster, this Volume Group must be added and integrated on cluster level. Therefore, we need to login to the web frontend of the cluster and add this under:

• Datacenter
• Storage
• Add
• LVM

In the new window some more details for the new LVM storage have to be defined:

• ID: shared_nvme01 (this can be any text and is jut an identifier)
• Base storage: Existing volume groups
• Volume group: shared_nvme01
• Content: Disk image, Container (may vary)
• Nodes: <Select all nodes that should use it>
• Enables: Yes
• Shared: Yes
• Wipe Removed Volumes: No

By pressing on Add this will be attached to the selected nodes as a new volume and can directly be used.

Conclusion

The utilization of NVMe over Fabrics (NVMe-oF) via TCP in addition with Proxmox VE in a virtualization environment presents a compelling solution for organizations looking at cost-effective yet high-performance storage architectures. This approach leverages the widespread availability and compatibility of Ethernet-based networks, avoiding the need for specialized hardware such as Fibre Channel or InfiniBand, which can be cost-prohibitive for many enterprises.

By integrating NVMe-oF with Proxmox, a popular open-source virtualization platform, users can benefit from significantly improved data transfer speeds and lower latency compared to traditional storage solutions. NVMe-oF may not only be used with Proxmox VE but also on other operating systems like FreeBSD and hypervisors like bhyve. This provides a great benefit for latency-sensitive workloads, such as virtualized database servers, where rapid access to data is critical for performance. The NVMe protocol is designed to exploit the full potential of solid-state storage technologies. When used over a network fabric using TCP, it can deliver near-local NVMe performance by being very cost-effective.

At your convenience, we’re available to provide more insights into NetApp storage systems, covering both hardware and software aspects. Our expertise also extends to open-source products, especially in establishing virtualization environments using technologies like Proxmox and OpenShift or in maintaining them with config management. We invite you to reach out for any assistance you require.

You might also be interested in learning how to migrate VMs from VMware ESXi to Proxmox VE or how to include the Proxmox Backup Server into your infrastructure.

Migrating VMs from VMware ESXi to Proxmox

In response to Broadcom’s recent alterations in VMware’s subscription model, an increasing number of enterprises are reevaluating their virtualization strategies. With heightened concerns over licensing costs and accessibility to features, businesses are turning towards open source solutions for greater flexibility and cost-effectiveness. Proxmox, in particular, has garnered significant attention as a viable alternative. Renowned for its robust feature set and open architecture, Proxmox offers a compelling platform for organizations seeking to mitigate the impact of proprietary licensing models while retaining comprehensive virtualization capabilities. This trend underscores a broader industry shift towards embracing open-source technologies as viable alternatives in the virtualization landscape. Just to mention, Proxmox is widely known as a viable alternative to VMware ESXi but there are also other options available, such as bhyve which we also covered in one of our blog posts.

Benefits of Opensource Solutions

In the dynamic landscape of modern business, the choice to adopt open source solutions for virtualization presents a strategic advantage for enterprises. With platforms like KVM, Xen and even LXC containers, organizations can capitalize on the absence of license fees, unlocking significant cost savings and redirecting resources towards innovation and growth. This financial flexibility empowers companies to make strategic investments in their IT infrastructure without the burden of proprietary licensing costs. Moreover, open source virtualization promotes collaboration and transparency, allowing businesses to tailor their environments to suit their unique needs and seamlessly integrate with existing systems. Through community-driven development and robust support networks, enterprises gain access to a wealth of expertise and resources, ensuring the reliability, security, and scalability of their virtualized infrastructure. Embracing open source virtualization not only delivers tangible financial benefits but also equips organizations with the agility and adaptability needed to thrive in an ever-evolving digital landscape.

Migrating a VM

Prerequisites

To ensure a smooth migration process from VMware ESXi to Proxmox, several key steps must be taken. First, SSH access must be enabled on both the VMware ESXi host and the Proxmox host, allowing for remote management and administration. Additionally, it’s crucial to have access to both systems, facilitating the migration process. Furthermore, establishing SSH connectivity between VMware ESXi and Proxmox is essential for seamless communication between the two platforms. This ensures efficient data transfer and management during migration. Moreover, it’s imperative to configure the Proxmox system or cluster in a manner similar to the ESXi setup, especially concerning networking configurations. This includes ensuring compatibility with VLANs or VXLANs for more complex setups. Additionally, both systems should either run on local storage or have access to shared storage, such as NFS, to facilitate the transfer of virtual machine data. Lastly, before initiating the migration, it’s essential to verify that the Proxmox system has sufficient available space to accommodate the imported virtual machine, ensuring a successful transition without storage constraints.

Activate SSH on ESXi

The SSH server must be activated in order to copy the content from the ESXi system to the new location on the Proxmox server. The virtual machine will later be copied from the Proxmox server. Therefore, it is necessary that the Proxmox system can establish an SSH connection on tcp/22 to the ESXi system:

• Log in to the VMware ESXi host.
• Navigate to Configuration > Security Profile.
• Enable SSH under Services.

Find Source Information about VM on ESXi

One of the challenging matters in finding the location of the virtual machine holding the virtual machine disk. The path can be found within the web UI of the ESXi system:

• Locate the ESXi node that runs the Virtual Machine that should be migrated
• Identify the virtual machine to be migrated (e.g., pgsql07.gyptazy.ch).
• Obtain the location of the virtual disk (VMDK) associated with the VM from the configuration panel.
• The VM location path should be shown (e.g., /vmfs/volumes/137b4261-68e88bae-0000-000000000000/pgsql07.gyptazy.ch).
• Stop and shutdown the VM.

Create a New Empty VM on Proxmox

• Create a new empty VM in Proxmox.
• Assign the same resources like in the ESXi setup.
• Set the network type to VMware vmxnet3.
  • Ensure the needed network resources (e.g., VLAN, VXLAN) are properly configured.
• Set the SCSCI controller for the disk to VMware PVSCSI.
  • Do not create a new disk (this will be imported later from the ESXi source).
• Each VM gets an ID assigned by Proxmox (note it down, it will be needed later).

Copy VM from ESXi to Proxmox

The content of the virtual machine (VM) will be transferred from the ESXi to the Proxmox system using the open source tool rsync for efficient synchronization and copying. Therefore, the following commands need to be executed from the Proxmox system, where we create a temporary directory to store the VM’s content:

mkdir /tmp/migration_pgsql07.gyptazy.ch
cd /tmp/migration_pgsql07.gyptazy.ch
rsync -avP root@esx02-test.gyptazy.ch:/vmfs/volumes/137b4261-68e88bae-0000-000000000000/pgsq07.gyptazy.ch/* .

Depending on the file size of them virtual machine and the network connectivity this process may take some time.

Import VM in Proxmox

Afterwards, the disk is imported using the qm utility, defining the VM ID (which got created during the VM creation process), along with specifying the disk name (which has been copied over) and the destination data storage on the Proxmox system where the VM disk should be stored:

qm disk import 119 pgsql07.gyptazy.ch.vmdk local-lvm

Depending on the creation format of the VM or the exporting format there may be multiple disk files which may also be suffixed by _flat. This procedure needs to be repeated by all available disks.

Starting the VM

In the final step, all settings, resources, definitions and customizations of the system should be thoroughly reviewed. One validated, the VM can be launched, ensuring that all components are correctly configured for operation within the Proxmox environment.

Conclusion

This article only covers one of many possible methods for migrations in simple, standalone setups. In more complex environments involving multiple host nodes and different storage systems like fibre channel or network storage, there are significant differences and additional considerations. Additionally, there may be specific requirements regarding availability and Service Level Agreements (SLAs) to be concern. This may be very specific for each environment. Feel free to contact us for personalized guidance on your specific migration needs at any time. We are also pleased to offer our support in related areas in open source such as virtualization (e.g., OpenStack, VirtualBox) and topics pertaining to cloud migrations.

Addendum

On the 27th of March, Proxmox released their new import wizard (pve-esxi-import-tools) which makes migrations from VMware ESXi instances to a Proxmox environment much easier. Within an upcoming blog post we will provide more information about the new tooling and cases where this might be more useful but also covering the corner cases where the new import wizard cannot be used.