Mounting File Systems From Windows Instances

Users of Windows Server 2012 R2 and later versions can mount a file system on any available drive letter using the mount target IP address and the file system export path.

The Windows NFS client must be installed on the instance from which you want to mount the file system.


Installing the Windows NFS client may require a restart of your system.

Access to NFS file systems requires UNIX-style user and group identities, which are not the same as Windows user and group identities. To enable users to access NFS shared resources, Windows client for NFS accesses file systems anonymously, using AnonymousGid and AnonymousUid. On brand new file systems, write permissions are only granted to the root user. The AnonymousGid and AnonymousUid identity values must be configured to allow write access.


Updating the 'AnonymousGid' and 'AnonymousUid' values require registry changes to your system.

After you have installed the NFS client and correctly mapped user identities, you can mount the file system to any available drive letter using the command line or Map network drive. You can access your file system through the chosen drive letter to write files.


  • The file system must have at least one export in at least one mount target. When you create a new file system, an export for the file system is created at the same time. See Creating File Systems for more information.
  • Correctly configured security rules for the mount target. See Security Rules for information about how security rules work in Oracle Cloud Infrastructure. Use the instructions in Configuring VCN Security Rules for File Storage to set up security rules correctly for your file systems.

When mounting file systems, the following mount option combination is not supported by the File Storage service:

  • soft when the file system is mounted with the read/write mount option (-o rw). This combination can cause corruption of your data.

The following mount options or mount option combinations are not recommended for use with the File Storage service:

  • soft when the file system is mounted with the read-only mount option (-o ro) and the timeo has been specified as less than 300 seconds. This combination can cause a profusion of I/O error responses.
  • rsize, or wsize. These options cause issues with performance.

When mounting file systems, Network Lock Manager (NLM) is enabled for file locking by default. The default requires no specified mount option. Typical NFS workloads function normally using the default.

Some applications might require you to specify the nolock mount option. Refer to your application documentation for best practices regarding this mount option.

Using Windows Command Prompt

To mount a file system from Windows Server Command Prompt

Using Windows File Explorer

To mount a file system from Windows Server File Explorer

Mounting File System Subdirectories

If your file system has an existing directory structure, you can mount any file system subdirectory. The subdirectory becomes the effective root directory at the mount point of the instance, and excludes sibling directories.

For example, suppose "FileSystem1" has an export path of /FileSystem1 and a directory structure like this:

This diagram shows an example directory structure and mount point.

The file system is exported from "MountTarget1" which has an IP address of

The following command mounts directoryA to drive letter X:

mount X:

Neither directoryB or FileB would be accessible from drive X.


Mounting a subdirectory to limit access to sibling directories is not sufficient to secure your file system. For information on security methods, see About Security.

To mount a file system subdirectory