NFS suddenly stopped working

Hi @ Kai ,

Welcome to Microsoft Q&A Platform.

If suddenly your NFS mount is up but suddenly showing an empty directory. Azure Blob NFS isn’t generally “down,”

Verify the blobs still exist :
Inn the Azure portal or with the CLI run:

az storage blob list  --account-name <account>  --container-name <container> --auth-mode login

You can also check the files in the Azure portal. If you do not see your files there, they may have been deleted or moved. You can review the Activity Logs of the storage account to verify any related operations.

If the files exist in Blob Storage but are not appearing in NFF, please follow the troubleshooting steps below:

Unmount/remount to clear client cache : Mount the container

sudo umount /mnt/nfs 
sudo mount -t nfs -o vers=3,nolock .blob.core.windows.net:/ /mnt/nfs 

# 

<storage-account-name>.blob.core.windows.net:/<storage-account-name>/<container-name>  /nfsdata    aznfs defaults,sec=sys,vers=3,nolock,proto=tcp,nofail,_netdev    0 0

sudo mount /nfs

“nolock” is required because Azure Blob NFS doesn’t support NLM locking.

Check network & firewall rules

• NFS v3 on Blob Storage only uses TCP 2049. Test connectivity:

nc -zv .blob.core.windows.net 2049

• Ensure no NSG or firewall is blocking 2049 end-to-end (on-prem → service endpoint or private endpoint).
• Mount the root of the container only (no subdirs).
• Beware of hidden characters if you copy/paste the command.

Review permissions & ACLs

• You need Storage Blob Data Contributor (or higher) on the account or container.
• If you enabled any named-user/group ACL entries, remove them – Azure Blob NFS can’t honor those and will block non-root users.
• Client prerequisites • Linux kernel ≥ 4.3 and nfs-utils (or equivalent) must be installed.
• Windows NFS clients are not supported – use WSL2 as a workaround if on Windows.

If after these steps your mount is still empty or you see errors (e.g., “access denied,” timeouts, “no such file or directory”), let us know the exact error message and any recent changes you made (mount command, network, storage account config).

Resolve common errors by following the link here

If the above steps did not help resolve your issue, please feel free to share the details in a private message so we can proceed with further troubleshooting over a Teams call. I am happy to connect with you on Teams to investigate and resolve the issue

Please "upvote" if the information helped you. This will help us and others in the community as well.

When i try to access the storage browser in the web, it is showing no items found for the NFS shares.

Here is the error i get when i try to remount

reason given by server: No such file or directory

Hi @ Kai ,

Thank you for your response.

If Azure Portal (Storage Browser) is also showing “no items found”, then this is not an NFS mount issue — it’s either:

NFS in Blob works at container level, not like folders.

• Make sure you are opening the correct container
• Not another empty container

Check using CLI (bypass portal):

az storage blob list  --account-name <account>  --container-name <container> --auth-mode login

If all the options are showing empty, please try uploading some test files and check if they appear in NFS.

If all files are suddenly not visible, please check the Activity Log in the Azure portal by navigating to Azure Portal → Storage Account → Activity Log

Apply the following filters:

• Delete Blob
• Delete Container
• Write operations

If any data was deleted, the corresponding operations will be visible in the logs.

Note: Also verify that you have the required permissions (e.g., Storage Blob Data Contributor) and check the storage account firewall settings to ensure proper access.

If still same issue please share the requested details in Private message for further troubleshoot.

Refer:

Mount Blob Storage by using the Network File System (NFS) 3.0 protocol
Known issues with Network File System (NFS) 3.0 protocol support for Azure Blob Storage

Please "upvote" if the information helped you. This will help us and others in the community as well.