#1 Global Leader in Data Resilience

Guest File Restore from Backup of Linux on Power Machine Fails to Mount

KB ID: 4572
Product: Veeam Backup & Replication
Veeam Agent for Linux
Published: 2024-04-18
Last Modified: 2024-05-09
mailbox
Get weekly article updates
By subscribing, you are agreeing to have your personal information managed in accordance with the terms of Veeam's Privacy Notice.

Cheers for trusting us with the spot in your mailbox!

Now you’re less likely to miss what’s been brewing in our knowledge base with this weekly digest

error icon

Oops! Something went wrong.

Please, try again later.

Challenge

When restoring files and folders from a Veeam Agent for Linux backup of a Linux on Power machine that was using the BTRFS filesystem, if a temporary helper appliance or non-Linux on Power machine is used, the mount operation step of the restore will fail with:

Fuse mount failed: Failed to mount: No such device
Failed to mount [btrfs] file system.
Unable to mount device [/dev/loop0] with filesystem [btrfs] to mount point

 

Error

Cause

This error occurs because Linux on Power uses a block size of 64 KiB for the BTRFS file system, which cannot be mounted by 64-bit Linux operating systems, which typically use a 4KiB block size.

Per BTRFS documentation:

Subpage support
Subpage block size support, or just subpage for short, is a feature to allow using a filesystem that has different size of data block size (sectorsize) and the host CPU page size. For easier implementation the support was limited to the exactly same size of the block and page. On x86_64 this is typically 4KiB, but there are other architectures commonly used that make use of larger pages, like 64KiB on 64bit ARM or PowerPC or 16KiB on Apple Silicon. This means filesystems created with 64KiB sector size cannot be mounted on a system with 4KiB page size.

 

Solution

On the Helper Host selection step of the Guest File Restore Wizard, select the original machine or another Linux on Power machine.

 

More Information

This error will also occur when mounting a volume created with the XFS file system with a 64 KiB block size.
To submit feedback regarding this article, please click this link: Send Article Feedback
To report a typo on this page, highlight the typo with your mouse and press CTRL + Enter.

Spelling error in text

This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.
Thank you!

Thank you!

Your feedback has been received and will be reviewed.

Oops! Something went wrong.

Please, try again later.

You have selected too large block!

Please try select less.

KB Feedback/Suggestion

This form is only for KB Feedback/Suggestions, if you need help with the software open a support case

By submitting, you are agreeing to have your personal information managed in accordance with the terms of Veeam's Privacy Notice.
This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.
Verify your email to continue your product download
We've sent a verification code to:
  • Incorrect verification code. Please try again.
An email with a verification code was just sent to
Didn't receive the code? Click to resend in sec
Didn't receive the code? Click to resend
Thank you!

Thank you!

Your feedback has been received and will be reviewed.

error icon

Oops! Something went wrong.

Please, try again later.