Update :
The Zentayal logs aren't very helpful with this particular issue.
I have managed to find a work-around for this, however it is still not clear to me why this is the way it is, or whether it is an oversight by the developers.
1. Login to the zentayal server and get to a shell; Switch to root user.
2. Mount the partition where u want the share to be. Setup correctly under /etc/fstab as follows. ( /u is my mountpoint for my 2nd disk ( partitioned /dev/sdb1 )
/dev/sdb1 /u ext4 errors=remount-ro,acl,user_xattr,usrquota,grpquota,acl 0 1
or UUID=54fc9f7f-d13d-4649-b104-1584d4e7cd96 /u ext4 errors=remount-ro,acl,user_xattr,usrquota,grpquota,acl 0 1
From terminal, make the mount point, mkdir /u, then do a mount -a , to mount the disk at /u.
3. Change the ownership of the mountpoint /u to root and the group to domain users.
chown root:domain\ users /u
4. Create a folder that you want to share. cd to /u
mkdir Folder1
5. Change the ownership and group of the folder
chown root:domain\ users Folder1
then
chmod 770 /u/Folder1
6. Now go to the zentayal web interface under File Sharing,. create a new share.
Share name = Folder1
Share Path = Select filesystem path, type in /u/Folder1.
Comment = Whatever you like
Tick Apply ACLS recursively.
7. Click Add, then Save Changes, the samba module should return success, i.e share created without any errors.
8. Add an ACL for the Folder1 share.
If there is any one who can update / or contribute to clarify or define this issue,, please feel free to do so.
Perhaps someone can shed some light on how and why this issue occurs.
References I used:
https://forum.zentyal.org/index.php?topic=21038.0 NOTE : I used root:domain\ users instead of ebox:ebox like mentioned in the above link.