Shares created on any directory under /ifs/.snapshot will not allow the users to change permission the share or export.
The share on that path will be read only and will not be changed to write or execute.

A storage snapshot is a set of reference markers for data at a particular point in https://dell.to/32KWFze Onefs these snapshots are stored under the path  "/ifs/.snapshot".
This is as per designed that .snapshot is always in read only format and we cannot change any permission on the .snapshot folder because we are not allowed to modify any security descriptor of read only file system,so creating a share on these paths will not allow end user to access the filesystem.
Below is the  example where we try to modify the permission using chmod comand from root user but we are not allowed to do that.

Example:- 
Halfpipe8011-1# pwd
/ifs/.snapshot

Halfpipe8011-1# id
uid=0(root) gid=0(wheel) groups=0(wheel),5(operator),10(admin),20(staff),70(ifs)

Halfpipe8011-1# chmod -R +a user root allow  dir_gen_all /ifs/.snapshot
chmod:  Could not set the security descriptor for SIQ-8f99f46001a5905225724af10acb3c60-latest:  Read-only file system
chmod: Could not set the security descriptor for xyz: Read-only file system

1)Its not recommended to create share or export on .snapshot but if you want to create you can copy the data of .snapshot folder locally to your folder where you can change the permission.

2)You can make .snapshot visible in smb using below commands:-

#isi smb shares modify --hide-dot-files=False --share=

"--hide-dot-files {yes | no} Hides files and directories that begin with a period ".".  but only if the snapshot lives within the share"

Issue

When you run a Robocopy job with the /B option (backup mode) to copy files from a Windows 2008 R2 server to an Isilon cluster, the security configuration information, such as Access Control Lists (ACLs) is not copied. Additionally, Robocopy returns one of the following errors:

ERROR 5 (0x00000005) Copying NTFS Security to Destination Directory Access is denied

ERROR 5 (0x00000005) Copying NTFS Security to Destination File Access is denied

Cause

This issue occurs because the /B option does not open the files to be backed up, which consequently prevents access to the security information of those files.

Solution

1. Ensure that the cluster is running OneFS 6.5.3.QFE.1032 or higher.
2. Enable "Run as Root" for the destination shares on the Isilon cluster for the users who will run the Robocopy job. For instructions, see How to set SMB users and groups to run as the root user on OneFS 6.5 and later,  Link Error 16475 .
    
3. Install the following hotfix from Microsoft on the Windows 7 or Windows Server 2008 R2 computer:
   https://dell.to/3KYpRUU.
   
   

   IMPORTANT!
   Ensure you download the correct version of the hotfix that applies to the version of Robocopy you have installed. To check which version of Robocopy is installed on the Windows computer:

   1. In Windows Explorer, navigate to C:\Windows\System32.
   2. Right-click the Robocopy.exe file and choose Properties.
   3. On the Details tab, check the File version entry.
      
       

Additional information

• Required configuration options for using Robocopy with an Isilon cluster,  Link Error 89794
• Microsoft TechNet Robocopy reference