VirtioFS Setup Guide for Ubuntu

[c4tom]

VirtioFS Setup Guide for Ubuntu on Proxmox

Introduction

This guide provides step-by-step instructions for setting up VirtioFS on an Ubuntu virtual machine running on Proxmox. VirtioFS is a shared file system that allows for high-performance file sharing between the host and guest systems.

Prerequisites

• Proxmox 8.4.x host
• Ubuntu 22.04 LTS virtual machine (https://community-scripts.github.io/ProxmoxVE/scripts?id=ubuntu2204-vm)
  • update kernel
• Proper permissions to modify VM configuration

Step 1: Configure VirtioFS in Proxmox

1. Shut down your Ubuntu VM if it's running.
2. Add VirtioFS shares to your VM configuration:
   • Open your VM's configuration file (typically at /etc/pve/qemu-server/VMID.conf)
   • Add the following lines for each share:

     virtiofs0: ShareName,size=4G
     

   • Example:

     virtiofs0: project
     virtiofs1: data
     

3. Enable the QEMU agent in the VM options if not already enabled:

   agent: 1
   

Step 2: Prepare Ubuntu Guest

1. Update your system and upgrade the kernel:

   # Update package lists
   sudo apt update
   
   # Upgrade all packages including the kernel
   sudo apt upgrade -y
   
   # Install the latest HWE (Hardware Enablement) kernel
   sudo apt install -y --install-recommends linux-generic-hwe-22.04
   
   # Reboot to apply the new kernel
   sudo reboot

   After rebooting, verify the new kernel version:

   uname -r

   You should see a kernel version 5.15.0-xx-generic or newer.

2. Install required packages:

   sudo apt install -y qemu-guest-agent

3. Ensure the VirtioFS kernel module is loaded:

   sudo modprobe virtiofs

   To make it persistent across reboots:

   echo "virtiofs" | sudo tee -a /etc/modules

Step 3: Create Mount Points

1. Create directories for your shares:

   sudo mkdir -p /mnt/project
   sudo mkdir -p /mnt/data

2. Set appropriate permissions (replace youruser with your actual username):

   sudo chown -R youruser:youruser /mnt/project
   sudo chown -R youruser:youruser /mnt/data

Step 4: Configure Automatic Mounting

1. Edit the fstab file:

   sudo nano /etc/fstab

2. Add the following lines to mount the shares at boot:

   # VirtioFS shares from Proxmox
   project /mnt/project virtiofs rw,nofail,noatime 0 0
   data /mnt/data virtiofs rw,nofail,noatime 0 0
   

3. Save the file and exit the editor.

Step 5: Mount the Shares

1. Mount all filesystems defined in fstab:

   sudo mount -a

2. Verify the mounts are working:

   df -h

   You should see your VirtioFS shares listed in the output.

Step 6: Verify Read/Write Access

1. Test write access to the shares:

   touch /mnt/project/testfile
   touch /mnt/data/testfile

2. Check if files were created:

   ls -la /mnt/project/
   ls -la /mnt/data/

Troubleshooting

1. If mounts fail on boot:

   • Check the system journal: journalctl -xe
   • Verify the VirtioFS module is loaded: lsmod | grep virtio
   • Check dmesg output: sudo dmesg | grep -i virtio

2. If you get permission errors:

   • Ensure the mount points are owned by the correct user
   • Check the share permissions on the Proxmox host

3. If the shares don't appear:

   • Verify the VM configuration in Proxmox
   • Check if the VirtioFS daemon is running on the host

Performance Tuning (Optional)

For better performance, you can add these options to your fstab entries:

• direct_io=1 - Bypass the page cache (good for large files)
• noatime - Don't update file access times
• nodiratime - Don't update directory access times

Example:

data /mnt/data virtiofs rw,nofail,noatime,nodiratime,direct_io=1 0 0
project /mnt/project virtiofs rw,nofail,noatime,nodiratime,direct_io=1 0 0

Conclusion

You have successfully set up VirtioFS shares between your Proxmox host and Ubuntu VM. The shares should now be accessible at the specified mount points and will be automatically mounted at boot.