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How Data ONTAP enables you to provide SMB client access to UNIX symbolic links

You must understand certain concepts about how Data ONTAP enables you to manage symbolic links. This is important to provide access to SMB users connecting to the Storage Virtual Machine (SVM).

A symbolic link is a file created in a UNIX environment that contains a reference to another file or directory. If a client accesses a symbolic link, it is redirected to the target file or directory that the symbolic link refers to.

Data ONTAP provides SMB clients the ability to follow UNIX symbolic links configured on the SVM. This feature is optional and you can configure it on a per-share basis with one of the following settings:

There are two types of symbolic links:

Relative
A relative symbolic link contains a reference to the file or directory relative to its parent directory. Therefore, the path of the file it is referring to should not begin with a slash (/). If you enable symbolic links on a share, relative symbolic links work without further configuration.
Absolute
An absolute symbolic link contains a reference to a file or directory in the form of an absolute path. Therefore, the path of the file it is referring to should begin with a slash (/). It is treated as an absolute path location of the file from the root of the file system. An absolute symbolic link can refer to a file or directory within or outside of the file system of the symbolic link. If the target is not in the same local file system, the symbolic link is called a widelink. If you enable symbolic links on a share, absolute symbolic links do not work right away. You must first create a mapping between the UNIX path of the symbolic link to the destination CIFS path. When creating absolute symbolic link mappings, you specify whether it is a local or widelink. If you create an absolute symbolic link to a file or directory outside of the local share but set the locality to local, Data ONTAP disallows access to the target.

Note that if a client attempts to delete a local symbolic link (absolute or relative), only the symbolic link is deleted, not the target file or directory. However, if a client attempts to delete a widelink, it might delete the actual target file or directory that the widelink refers to. Data ONTAP does not have control over this because the client can explicitly open the target file or directory outside the SVM and delete it.