The Promise SR3 A-Class client release introduces Extended Access Control List (EACL) support for Mac OS. Before this release, we had only supported standard POSIX permissions. While this may have sufficed for some users, others required more granular control of their A-class file system permissions. Thus, we’ve implemented support for EACLs with this release. We now support multiple users and multiple groups as well as inheritance. Subfolders/Files may now have different permissions than their parent folders. 

In order for EACLs to work properly with the A-class file system, the client must be set to “Squash No-Root” in the Access Settings page. This is accomplished by logging into the A-class GUI and navigating to File System > Folder > Access Settings (using the “gear” drop-down menu):

Save and confirm the setting for each one of the clients. 

Note: If there are existing files and folders created on the A-class using the “Squash All” setting, the permissions for these existing files and folders will need to be manually changed using Mac OS command line. Please contact Promise Technical Support for assistance. 

You must also enable the Extended ACL setting on the VtrakFSClient. To access this setting,you need to first open the VtrakFSClient application and click on the server IP. 

Note* If your file system is currently mounted, please unmount the file system, make the setting change, and then remount for the change to take effect.

You’ll then see your mount points in the right-hand window. Select the mount point and then there will be various optional settings available. Navigate to Advanced > Extended ACL and then enable this setting:


Permissions for the A-class files system can be set or modified through the “Get Info” function when browsing to files and folders. Then expand the Sharing and Permissions menu:



Simply click on the “lock” and then use the “+” or “-“buttons to Add or Remove users or groups and then assign their Privileges. 

For more information, please see the Apple Knowledge Base article linked below, or contact Promise Technical Support: