A Guide to Migrating from VMware to Proxmox for CIOs and CTOs

Aurélien Violet

Oct 1, 2024 • 10 min

A Guide to Migrating from VMware to Proxmox for CIOs and CTOs

Originally published on Le Monde Informatique.

In light of VMware’s pricing policy changes, many companies have already started migrating to alternative solutions like Proxmox VE (Proxmox Virtual Environment). We’ve supported french companies across various industries, such as Oodrive, XBTO, Weka, and IMIO.be, in making this transition. A migration of this nature presents concrete challenges, both technical and organizational, which we aim to share in this experience report.

Monkey Enix flying between two balloons with Proxmox and Enix logos

What are the key considerations that companies face? What are the steps to a smooth migration to Proxmox with no impact on the services running on their virtualization platform? Three main aspects are highlighted: the preparatory phase with its technical considerations, the change management process, and the migration phase itself.

A Crucial Step: The Audit and Preparation Phase

For most companies, migrating to Proxmox is not just about meeting virtual machine (VM) needs. Whether their platform is on-premise or in a private cloud, it includes fundamental infrastructure functionalities such as storage, specific network and security needs, or encrypted backups. Prior to migration, a comprehensive audit of the VMware services used and the existing infrastructure is essential. This phase helps validate the project’s feasibility and define the architecture and technical alternatives for each functionality on the Proxmox-based target platform.

Beyond functionality, special attention must be given to the platform’s integration into its ecosystem: identifying third-party software that relies on VMware APIs to port them over to Proxmox. Another crucial point is the control plan. This involves analyzing how the platform is managed, consumed, and monitored by the technical teams.

This preparation phase can also be an opportunity for companies and their CIOs to enhance the functionality of their platform. “If you’re going to switch virtualization technologies following VMware’s acquisition by Broadcom, it’s an excellent opportunity for modernization: streamline the underlying infrastructure to reduce recurring costs, add a disaster recovery plan (DRP), improve backups, increase robustness with high availability and better security, or even outsource operational management to focus on core business activities,” suggests Aurélien Violet, Marketing Director at Enix.

Beyond Proxmox Virtualization: Recurring Technical Challenges

While each migration has its unique aspects, several recurring technical challenges can be identified. First, it’s necessary to define the design of the Proxmox VE virtualization clusters and the overall architecture: the type of deployment (on-premise, third-party hosting or cloud, hybrid), the chosen architecture (single-site, multi-site), the number and configuration of servers to be used in the Proxmox clusters, their distribution across sites, and so on.

At this design stage, it’s crucial to thoroughly consider the hardware aspect of the target platform. What types and specifications of servers should be used to achieve the desired performance? Is it possible to reuse existing hardware from the VMware platform, or will new hardware be partially or fully required? “Based on Linux, Proxmox VE is compatible with almost any type of hardware. In the vast majority of our client migration projects, we were able to reuse all or part of their servers,” confirms Aurélien Violet. “This broad compatibility is key. Proprietary solution providers sometimes try to discourage the use of open source by citing the lack of official hardware certification. To us, this is a well-known scaremongering tactic, summarized by the acronym FUD (Fear, Uncertainty, and Doubt).”

Another crucial point to consider is storage for Proxmox VMs and backups. Most often, the Ceph open-source technology, which is robust and widely deployed, is used, with various implementations possible: hyperconverged or not, integrated into the Proxmox interface or installed separately. There are also high-performance proprietary solutions that have long committed to perfect integration with Proxmox, such as BlockBridge. Existing specialized storage appliances, often requiring significant investments, can also be reused on the new platform.

For encrypted backups, the Proxmox team offers Proxmox Backup Server (PBS), a proven open-source solution that provides support services without licensing fees. It covers the backup needs of most companies and integrates easily with Proxmox VE virtualization. For more advanced needs, Veeam has announced support for Proxmox in its Data Platform v12.2 solution. “This is further proof of Proxmox’s maturity and reliability in production,” says Enix’s Marketing Director. “We’ve already tested it in operational conditions since the beta phase.”

When it comes to networking, no two companies are the same. A case-by-case assessment is necessary. In many organizations, different teams handle networking and virtualization. Where a dedicated network team exists, replacing VMware generally has a limited impact: a significant portion of network management occurs outside the VMware ecosystem, using specialized solutions, either open-source like VyOS or proprietary appliances like Palo Alto, Fortinet, Arista vEOS, etc. These can mostly be retained with the new Proxmox platform.

For those using network features tightly integrated with VMware, it’s important to ensure these services can be replicated around the virtualization core. Installing machines on virtual local area networks (VLANs) is a simple task that requires mapping what was deployed on VMware and replicating it in Proxmox. For routing features, particularly those included in VMware NSX-T, equivalents can be added to Proxmox. “At Enix, we install routers in the virtualization solution to bridge networks, followed by firewalls, etc.,” explains Sébastien Wacquiez, Managing Partner at Enix. “Additionally, Proxmox’s SDN capabilities have recently been improved, bridging much of the gap with VMware’s networking features, though it’s not yet fully equivalent.”

Properly Managing Proxmox Platform Operations

Another crucial aspect is the processes and tools for managing the target platform, meaning everything related to the platform’s operation. On the client side, platform administration should be as autonomous as possible, whether via Proxmox VE’s quality interface, scripts, or Infrastructure as Code (IaC) tools like Ansible or Terraform. The same applies to platform alerting and monitoring, using technologies like Prometheus or Grafana.

“Ultimately, with training or skill reinforcement, many companies can handle their migration independently. And if expertise is lacking, there are numerous French open-source and Proxmox specialists available,” assures Aurélien Violet, who also mentions the availability of packaged and managed solutions like their Proxmox Private Cloud (PPC) service, created to facilitate the switch from VMware to Proxmox, deployable on-premise or in the cloud. He adds, “We’re changing the model from VMware’s licensing structure: after evaluating our clients’ migrations, the additional cost of support and managed services is significantly lower than the savings on licenses, plus the managed service includes 24/7 support that goes far beyond just vendor support.”

A Prerequisite for Proxmox migration: Change Management

Alongside technical considerations, one of the main organizational and managerial challenges of migration is to ensure team buy-in: explain why the company is moving away from VMware and choosing a less packaged solution like Proxmox, present the benefits of the new solution, support skill development, potentially strengthen the teams with new engineers, or rely on a partner who can provide reassurance about the technology.

“Our goal is to eliminate the risks associated with VMware and help companies migrate to secure environments, stopping cost overruns and financial risks, and reclaiming their technological and operational sovereignty,” explains Enix’s Marketing Director. “Our role isn’t just to migrate and manage the new platform; we reassure teams that they can migrate their infrastructure without disrupting services.” This phase typically takes time, especially for very large organizations, where it’s necessary to convince and support multiple different teams, particularly those that use and manage the platform daily.

Beyond team support and training, an effective project organization must be established early in the preparation phase. This ensures coordination between the teams managing the platform and the teams responsible for middleware and business services, as well as with any external partners. This organization must guarantee the careful planning and tracking of the migration of the company’s services to the Proxmox platform.

Migrating Services: Inventory, Methodology, Procedures, and Import Tools

Before the actual VM and service migration, the target platform, based on Proxmox, must be fully installed and monitored as defined in the preparation phase. During the migration phase, the infrastructures run “in parallel”: the initially empty target platform will gradually host VMs migrated from VMware. To transfer the VMs, both platforms must be interconnected, allowing services to run on either platform during the migration.

At the same time, a detailed inventory of existing VMs is required. To minimize operational downtime, this inventory should be conducted as close as possible to the actual migration of the VMs, preferably in stages, by service type or user entity, rather than as a single global inventory.

A migration methodology must also be defined, including at least a method for copying VMs between platforms to ensure service continuity, as well as managing backups, network integration, monitoring, etc. Sébastien Wacquiez, who closely followed these migrations, notes: *“We’ve historically

used our internal tools for copying VMs. Since March 2024, an official import tool was developed by the Proxmox team, allowing VMs to be migrated while they continue to run.”* He adds that the Veeam support for Proxmox could simplify the process: *“For companies that want this type of backup solution, we can use it to ‘drive’ the migration of VMware ESXi VMs to Proxmox VMs.”*

To streamline the migration process, it’s better to avoid migrating all virtual machines at once, opting instead for a progressive approach. “After helping our client migrate their first VMs, we usually empower their teams to copy the remaining VMs according to their schedule and service constraints,” emphasizes the manager. Furthermore, to minimize risks to service availability, the migration methodology is first validated on test VMs and then applied to the company’s less critical applications. Finally, the entire process must be continuously verified through monitoring and metrics at the application level.

A Relatively Short Effective Proxmox Migration Duration

The duration of migration projects varies depending on the complexity of the platform, the VMware services used, and the applications involved. “In recent migration projects to Proxmox with companies of varying sizes, the timeframe turned out to be shorter than anticipated. In reality, the preparation phase is the longest, while the technical implementation is relatively brief,” notes Sébastien Wacquiez.

For example, a major migration project from VMware to Proxmox completed for a leading European telecommunications company took a total of a year and a half. Twelve months were dedicated to the decision-making, team preparation, and technical training. “We had to convince them,” the manager explains. “Technical demonstrations validated the migration’s feasibility and overcame internal resistance. It’s understandable to hesitate to change a system you know well, especially for an open-source solution sometimes incorrectly perceived as less reliable.”

Then, the entire technical implementation took just six months: two months to install the new bare-metal servers and Proxmox clusters, one month to interconnect the VMware and Proxmox solutions, and three months for the actual migration of applications hosted on their clusters, comprising several thousand virtual machines.

For simpler platforms, with available expertise and rapid decision-making, VMware to Proxmox migrations can often be much shorter, taking between 2 and 3 months.

Key Considerations Before and During Migration

Specific considerations, often non-technical, have been identified during migrations. For example, the platform certification aspect. According to Sébastien Wacquiez, “some companies that have had specific points of their VMware infrastructure certified must ensure that the audit or certification remains valid on Proxmox. Otherwise, they will need to re-certify the new platform.”

Another common concern is the difficulty companies face in accurately inventorying the virtual machines used by their teams across various departments. “It’s not uncommon for IT departments to report 2,000 active VMs, with sometimes half of them having unclear purposes. You could call these ‘shadow VMs,’ much like ‘shadow IT,’” notes Aurélien Violet, Enix’s Marketing Director. “A migration like this can also be an opportunity to rationalize infrastructure needs, resulting in additional cost savings.”

These considerations, though important, are regarded as minor by the managed services provider when executing the migration project, as long as they are anticipated and addressed diligently.