My Journey: Transition from VMWare ESXi 7 to Proxmox 9

After running VMWare ESXi for over 5 years in my homelab, I recently completed the migration to Proxmox 9. This wasn't a decision I made lightly—with 30+ VMs running various Linux distros, the migration required careful planning and execution. Here's my complete journey and the lessons learned along the way.

My Homelab Journey Background

I started my homelab journey in 2020, coming from a VMWare Workstation Player background. Naturally, VMWare ESXi 7 was my go-to choice for the hypervisor—it was the latest version available and felt like a natural progression.

The Hardware Evolution

My journey began with modest hardware:

• Initial Setup (2020): Intel NUC8I7BEH with 32GB RAM
• Hardware: Perfect for a beginner homelab
• Duration: Ran this setup for about 18 months before upgrading

As my homelab needs grew, I moved to higher-specification hardware from Supermicro with AMD Epyc 8 core processor while sticking with ESXi 7. By late 2023, I was managing 30+ VMs, mostly Linux distributions serving various purposes in my lab environment.

The Turning Point: VMWare Acquisition

The game changed in late 2023 when Broadcom acquired VMWare. The free version of ESXi was discontinued, leaving many homelabbers like myself in a difficult position. While ESXi 8 became available as a free version in April 2025, I had already started considering alternatives.

Why I Chose Proxmox

During my 5+ years with ESXi, I kept hearing about Proxmox VE—an open-source hypervisor that seemed to offer compelling advantages:

Key Motivating Factors

1. Open Source: No licensing uncertainties or vendor lock-in
2. LXC Container Support: Native support for both VMs and containers
3. Comprehensive Management: Integrated backup, monitoring, and clustering
4. Community Support: Active development and community backing

However, I was initially reluctant to migrate because:

• Scale: 30+ VMs represented significant investment in configuration
• Complexity: Migration isn't a simple one-click process
• Time Investment: Required immense planning and execution time

Step 1: Planning for Migration

The planning phase was crucial. With 30+ VMs, I couldn't afford downtime or data loss.

Pre-Migration Assessment

1. VM Inventory

   • Documented all 30+ VMs with their purposes
   • Catalogued resource allocations (CPU, RAM, storage)
   • Identified critical vs. development VMs
   • Listed network configurations and dependencies

2. Infrastructure Requirements

   • Verified hardware compatibility with Proxmox
   • Planned storage layout and naming conventions
   • Designed network bridge configurations
   • Created migration timeline and rollback plans

Migration Strategy

I decided on a phased migration approach:

• Phase 1: Non-critical development VMs
• Phase 2: Testing and validation VMs
• Phase 3: Production and critical services

Step 2: Actual Migration Process

Installing Proxmox 9

1. Fresh Installation - Clean Proxmox 9 installation with initial networking and storage configuration
2. Network Configuration - Created Linux bridges matching ESXi port groups with VLAN tagging

VM Migration Methods

Method 1: Using Proxmox Import Wizard

Proxmox provides a built-in import wizard, but it's not a complete solution:

# Example import command (simplified)
qm importovf 100 /path/to/vm.ovf local-lvm --format qcow2

Method 2: Manual Export/Import Process

For better control, I used a manual process:

# Convert VMDK to qcow2
qemu-img convert -f vmdk -O qcow2 source-disk.vmdk /path/to/storage/vm-100-disk-0.qcow2

# Create VM configuration
qm create 100 --name "migrated-vm" --memory 2048 --sockets 1 --cores 2
qm set 100 --scsi0 local-lvm:vm-100-disk-0,format=qcow2

Step 3: Post-Migration Configurations

This was where the real work began. Simply importing VMs wasn't enough—each required specific configurations.

Essential VM Adjustments

# Update VM hardware settings
qm set 100 --cpu cputype=host  # Better performance
qm set 100 --balloon 0         # Disable memory ballooning if needed
qm set 100 --agent 1           # Enable Qemu Guest Agent

Linux VM Specific Changes

Most of my VMs were Linux distributions, requiring these adjustments:

Install Qemu Guest Agent

# Ubuntu/Debian
sudo apt update && sudo apt install qemu-guest-agent
sudo systemctl enable qemu-guest-agent

# CentOS/RHEL
sudo yum install qemu-guest-agent
sudo systemctl enable qemu-guest-agent

Remove VMWare Tools

# Clean removal of VMWare tools
sudo vmware-uninstall-tools.pl

Step 4: Final Stage - Running VMs Seamlessly

Performance Optimization

1. CPU Configuration - Set CPU type to host for better performance
2. Storage Performance - Configured appropriate cache settings and I/O threads
3. Memory Management - Optimized memory allocation and ballooning settings

Backup Configuration

One major advantage of Proxmox is integrated backup:

# Configure automated backups
vzdump 100 --storage backup-storage --mode snapshot --compress gzip

Lessons Learned and Best Practices

What Worked Well

• Phased Approach: Migrating in phases reduced risk and stress
• Documentation: Thorough documentation saved time troubleshooting
• Testing Environment: Having a test Proxmox instance helped validate processes

Challenges Faced

• Time Investment: Migration took much longer than initially estimated
• Network Configuration: Required careful attention to bridge and VLAN setup
• VM Tools: Removing VMWare tools and installing Qemu agents took time

The Results: Was It Worth It?

After completing the migration of all 30+ VMs, I can confidently say yes, it was worth it:

Benefits Realized

• Cost Savings: No licensing fees or vendor dependency
• Enhanced Features: Better backup integration, LXC containers, clustering
• Performance: Comparable or better performance than ESXi
• Flexibility: Open-source platform with active development
• Peace of Mind: No concerns about future licensing changes

Conclusion

Migrating from VMWare ESXi 7 to Proxmox 9 with 30+ VMs was a significant undertaking that required careful planning and execution. While the process wasn't trivial, the benefits of an open-source, feature-rich virtualization platform have made it worthwhile.

The key to success was treating this as a project, not a quick task. Proper planning, phased execution, and allowing time for post-migration optimization were crucial factors in achieving a successful migration.

Timeline Summary: 5+ years on ESXi → 1 month planning and migration → Successfully running on Proxmox 9

The migration journey has not only saved me from licensing concerns but also opened up new possibilities for my homelab growth and experimentation.

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