Before attaching your Network File Storage (NFS) share to an Autonomous Database, ensure that:

• The Autonomous Database version is 19.18 or later to use NFSv3 and 19.23 or later for NFSv4.
• The customer-provided NFS is network accessible from Autonomous VM Cluster nodes.
• The NFS-mounted file system is readable and writable by the oracle operating system user on all the Autonomous VM cluster nodes.
• If permissions are being controlled at the user level, then the uid:gid of the oracle user for the Autonomous VM cluster is 1001:1001.

Use DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM to attach a file system to a directory in your Autonomous Database.

1. Create a directory or use an existing directory to attach the external file system in your Autonomous Database. You must have WRITE privilege on the directory object on your Autonomous Database instance to attach a file system to a directory location in the database.

   For example, the following command creates the database directory named NFS_DIR and creates the file system directory nfs:

   CREATE DIRECTORY NFS_DIR AS ‘nfs’;

   See Create a Directory for more information.

2. Run DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM to attach a file system to a directory in your Autonomous Database. To run this procedure, you must be logged in as the ADMIN user or have EXECUTE privilege on DBMS_CLOUD_ADMIN.

   • By default, DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM uses NFSv3. However, you can choose to explicitly use the params parameter and specify the nfs_version with value 3 to specify NFSv3.

     BEGIN
     DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM (
         file_system_name      => 'NFS',
         file_system_location  => 'myhost.sub000445.myvcn.oraclevcn.com:/results',
         directory_name        => 'NFS_DIR',  
         description           => 'Source NFS for sales data'                                   
     );END;                                                                          
     /

   • To use NFSv4, include the params parameter with DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM and specify the nfs_version with value 4 to specify NFSv4.

     BEGIN
       DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM (
         file_system_name => 'NFS',
         file_system_location => 'myhost.sub000445.myvcn.oraclevcn.com:/results',
         directory_name => 'NFS_DIR',
         description => 'Source NFS for sales data',
         params => JSON_OBJECT('nfs_version' value 4)
       );
     END;
     /

   The examples shown above attach the network file system specified in the file_system_name parameter to the Autonomous Database.

   The file_system_location parameter specifies the location of the file system. The value you supply with file_system_location consists of a Fully Qualified Domain Name (FQDN) and a file path in the form: FQDN:file_path.

   For example:

   • FQDN: myhost.sub000445.myvcn.oraclevcn.com
   • File Path: /results

   The directory_name parameter specifies the directory name in the Autonomous Database where you want to attach the file system. This is the directory you created in Step 1, or another directory you previously created.

   The description parameter specifies the description for the task.

   The params parameter is a JSON value that specifies an additional attribute nfs_version, whose value can be either 3 or 4 (NFSv3 or NFSv4).

Notes for using DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM:

• Oracle Cloud Infrastructure File Storage uses NFSv3 to share. See Overview of File Storage for more information.

• If you attach to non-Oracle Cloud Infrastructure File Storage systems, the procedure supports NFSv3 and NFSv4.

• If you have an attached NFS server that uses NFSv3 and the NFS version is updated to NFSv4 in the NFS server, you must run DBMS_CLOUD_ADMIN.DETACH_FILE_SYSTEM and then DBMS_CLOUD_ADMIN.ATTACH_FILE_SYSTEM (using the params parameter with nfs_version set to 4. This attaches NFS with the matching protocol so that Autonomous Database can access the NFSv4 Server. Without detaching and then reattaching, the NFS server will be inaccessible and you may see an error such as: "Protocol not supported".

See ATTACH_FILE_SYSTEM Procedure for more information.

For Example:

SELECT file_system_name, file_system_location, directory_path                      
   FROM dba_cloud_file_systems
   WHERE file_system_name = 'FSS';

Example showing a write a file on an attached file system using UTL_FILE:

DECLARE
  l_file         UTL_FILE.FILE_TYPE;
  l_location     VARCHAR2(100) := 'FSS_DIR';
  l_filename     VARCHAR2(100) := 'test.csv';
BEGIN
  -- Open the file.
  l_file := UTL_FILE.FOPEN(l_location, l_filename, 'w');
   
  UTL_FILE.PUT(l_file, 'Scott, male, 1000');
 
  -- Close the file.
  UTL_FILE.FCLOSE(l_file);
END;
/

Example showing a read a file on an attached file system using UTL_FILE:

DECLARE
  l_file         UTL_FILE.FILE_TYPE;
  l_location     VARCHAR2(100) := 'FSS_DIR';
  l_filename     VARCHAR2(100) := 'test.csv';
  l_text         VARCHAR2(32767);
BEGIN
  -- Open the file.
  l_file := UTL_FILE.FOPEN(l_location, l_filename, 'r');
 
  UTL_FILE.GET_LINE(l_file, l_text, 32767);
 
  -- Close the file.
  UTL_FILE.FCLOSE(l_file);
END;
/

Example showing list files on an attached file system using DBMS_CLOUD.LIST_FILES:

SELECT object_name FROM DBMS_CLOUD.LIST_FILES('FSS_DIR');

See the following for more information:

• UTL_FILE
• LIST_FILES Function

Use the DBMS_CLOUD_ADMIN.DETACH_FILE_SYSTEM procedure to detach a file system from a directory in your Autonomous Database.

Run DBMS_CLOUD_ADMIN.DETACH_FILE_SYSTEM procedure to detach a file system from a directory location in your Autonomous Database. To run this procedure, you must be logged in as the ADMIN user or have the EXECUTE privilege on DBMS_CLOUD_ADMIN.

BEGIN
  DBMS_CLOUD_ADMIN.DETACH_FILE_SYSTEM (
    file_system_name      => 'NFS'                                       
  );END;                                                                          
/