Use ReFS or NTFS on a single USB drive backup repository?

[jeffshead]

I just wanted to post my +1yr experience dealing with a ReFS repository on a Windows 2019 (1809) server.

Over a year ago, I added another backup job as a precaution for ransomware attacks. It utilizes a 14TB USB drive which is powered on/off and connected/disconnected via script before/after the backup job. Back then, I was debating on using NTFS or ReFS for the repository on the USB drive. I tested both and found that the backups completed much faster when the drive was formatted NTFS. However, I ended up reformatting to ReFS due to the recommendations on the Veeam forum.

Everything had been working well with the exception of several monthly health check failures. I ran manual scans for the first few occurrences which verified the corruption. So I just started creating a new, full backup when a failure occurred rather than messing with testing the backup. A few months later, I decided to go back to NTFS and I have encountered zero issues since then and I have been enjoying much quicker backups.

Speaking strictly from my personal situation and experience, I have to say that NTFS is a better option for single USB drive repositories. I don't know if upgrading to Windows 2022 for a newer version of ReFS would make any difference. ReFS excels at synthetic full creation so that kinda offset the longer backup times but none of that matters if the backup is not usable.

Also, for those that have encountered the Incorrect function. Agent failed to process method {ReFs.SetFileIntegrity} error, as I did when I went from ReFS to NTFS, I simply right-clicked on the repository, selected Properties... and I walked through all of the steps in the setup wizard; I did not change any settings. Doing this caused Veeam to recognize that the drive's file system is NTFS, not ReFS. I did not have to recreate the backup job, restart Veeam services or add any registry hacks to the server as others have posted as a workaround, in other threads.

Hoping this info saves time and grief for others.

Cheers!

[Mildur]

Hi Jeff

Thanks for sharing your experience.

Please note, ReFS should never be used on a usb disk. ReFS on removable media is not supported by microsoft:
https://learn.microsoft.com/en-us/windo ... -this-time

However, I ended up reformatting to ReFS due to the recommendations on the Veeam forum.

Could you maybe share with me the topic with the recommendation to format an usb disk with reFS?

Thanks
Fabian

[albertwt]

Hi Jeff,

I normally use the NTFS best practice to format the USB drive VB Repository with the 64K cluster sizes to reduce fragmentation.

This is as described in: https://techcommunity.microsoft.com/t5/ ... a-p/425960

Hope this helps.