@Chris Beuckeleers
It's no problem at all, and I apologize for the inconvenience the re-tagging caused!
I spoke with both our Azure AD and Azure Storage teams and as of right now, we don't have any Azure features that would allow you to have an on-premise Linux file server using O365 authentication. Since this currently isn't possible, I'd recommend leveraging our User Voice forum so our engineering team can look into implementing this feature.
Here are some of the links we found, which requires Azure Files:
Overview - on-premises Active Directory Domain Services authentication over SMB for Azure file shares
Microsoft 365 integration with on-premises environments
Use Azure Files with Linux
How to: NFS Kerberos Configuration with Linux Client
Office365 Tech Community
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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