Proxmox VE ZFS to EXT4

Rebuilding My Homelab: Transitioning from ZFS to EXT4 on Proxmox VE

Introduction

I have a Lenovo ThinkStation P3 Tiny that serves as my starter homelab machine. It’s compact but decently powered with:

• 2 NICs with 5 ports
• 1TB SSD
• 16GB DDR5 RAM

I initially installed Proxmox VE (PVE) using ZFS as the file system by selecting RAID0, thinking its features like snapshots and data integrity would be beneficial. However, I soon realized it was a big mistake. ZFS is incredibly RAM-hungry, and with only 16GB of RAM, my homelab couldn’t handle many VMs and services running simultaneously.

My Initial Setup

• PVE on ZFS using RAID0
• pfSense VM for firewall management
• Proxmox Backup Server (PBS)
• Ubuntu Server VM running Docker and Portainer

While I had grand plans for more services, the ZFS overhead severely limited my system’s capabilities. I decided to reinstall PVE using EXT4 to free up RAM and streamline performance.

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Why Switch from ZFS to EXT4?

• Lower RAM Usage: ZFS consumes a lot of RAM. Switching to EXT4 would free up more memory for VMs.
• Better Performance: On a single SSD setup, ZFS’s advantages are less impactful, while EXT4 offers better general performance.
• Simplicity: Managing ZFS’s tuning and overhead added unnecessary complexity to my homelab.

While Btrfs was an alternative, I opted for the tried-and-true EXT4 with LVM-Thin for flexibility and snapshots.

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The Reinstallation Journey: Step-by-Step

1. Initial Reinstallation Attempt

I popped in my old PVE USB installer and went for a fresh install. That’s when the problems started:

• Error Message:

  “Failed to prepare EFI boot using grub on ‘/dev/nvme0n1p2’. Unable to install the EFI bootloader. Warning: Please specify –no-rename explicitly.”

I was stuck.

2. Finding the Right Terminal Access

Getting to a working command prompt was tricky. I finally booted the PVE installer in debug mode and accessed a terminal with root@proxmox. This terminal actually worked, unlike the post-install terminal (Ctrl + Alt + F3), which threw errors like:

“System has not been booted with systemd.”

3. Troubleshooting Attempts

Here’s a chronological breakdown of everything I tried before finding the real solution:

• Tried installing Linux Mint: The installation failed.
• Re-downloaded PVE ISO: Thought the issue might be the ISO. It wasn’t.
• USB Installer Issues: I used Rufus to create the bootable USB, and while it defaulted to GPT, that wasn’t the root cause. The installer was fine.
• Debated sticking with ZFS: I quickly abandoned that thought.
• Boot Settings Adjustments: I explored various BIOS settings.
• Legacy BIOS Mode: I considered switching to Legacy mode but couldn’t find the option in BIOS on this new machine.
• Secure Disk Wipe: Performed a secure wipe from BIOS—installation still failed.
• EFI Variables Cleanup: Tried deleting EFI variables to clean out EFI dump files but found nothing useful.
• Checked EFI Vars Storage: Ran df -h /sys/firmware/efi/efivars:

  Filesystem: efivars

  Size: 192K

  Used: 191K

  Avail: 0

  Use%: 100%

4. Hardware Troubleshooting

Out of desperation, I followed Lenovo’s Hardware Maintenance Manual to open up the ThinkStation P3 Tiny:

• Located the fan and CMOS battery underneath.
• Removed and reinserted the CMOS battery for a hard reset.

While this was a great hardware learning experience, it didn’t fix the installation issue.

5. The Breakthrough: BIOS Reset

Finally, I decided to reset the BIOS to factory settings. This did the trick! After the reset, I no longer faced EFI bootloader errors, and the installer proceeded.

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Manual Partitioning with fdisk

After the BIOS reset, I manually partitioned the SSD using fdisk:

1. Deleted Old Partitions:

   sudo fdisk /dev/nvme0n1
   d  # Delete partition 1
   d  # Delete partition 2
   d  # Delete partition 3
   

2. Created New Partitions:
   • EFI Partition:

     n  # New partition
     Partition type: EFI (code ef)
     First sector: default
     Last sector: +512M
     

   • Linux Root Partition:

     n  # New partition
     Partition type: Linux LVM (code dont remember)
     Use the remaining space
     

3. Verify Partitions with lsblk:

   lsblk
   

   • nvme0n1p1: EFI partition
   • nvme0n1p2: Linux LVM (not mounted initially)
4. Format Partitions:

   sudo mkfs.fat -F32 /dev/nvme0n1p1  # EFI Partition
   sudo mkfs.ext4 /dev/nvme0n1p2      # Root Partition
   

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LVM Configuration

Since the root partition was set to LVM, I proceeded to configure it:

1. Scan for Physical Volumes:

   sudo pvscan
   

2. Display Volume Groups:

   sudo vgdisplay
   

   • Found volume group pve.
3. Logical Volume Check:

   sudo lvdisplay
   

   • Initially, no logical volumes were listed.
4. Rescanning:

   sudo lvscan
   

After confirming the LVM setup, I re-ran the PVE installation, and this time, it completed successfully!

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Final Steps

After the successful installation, I powered down the system:

sudo shutdown now

I took a much-needed break after a long night of troubleshooting. With everything documented here, I’m now ready to rebuild my homelab services and VMs on this lean, EXT4-based setup.

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Conclusion

This was an intense troubleshooting journey, but it’s a testament to the complexity of homelab setups and how patience and methodical steps can resolve even the most frustrating issues. I hope this documentation helps me (and maybe others) in future homelab adventures!

Now, time to get back to building out my VMs and services. Onward!