Please consider moving this question as-is (no need to recreate) to the proper forum for maximum visibility.  Questions written to the users' own "Discussions" space don't get the same amount of attention and can go unanswered for a long time.

You can do so by selecting "Move" under ACTIONS along the upper-right.  Then search for and select: "Celerra Support Forum" or "VNX Support Forum".

Celerra Support Forum

VNX Support Forum

This has hints of having similarity to the following user's experience:

Cannot access CIFS shares after installing 2008R2 server.

Quite a bit was discussed and recommended (unjoin and rejoin to domain, review of SPN's, reviewing NTLM vs Kerberos, etc), but it probably would require a network trace and reviewing with EMC support to resolve.  I would suggest reviewing the comments and recommendations in the post to see if maybe there is anything that you can apply to your troubleshooting.  Ultimately though, it may be best for EMC Support to review and may be elusive enough to require packet captures.

Thank you for the response.  I have moved this to the celerra support forum.

Try running nas_checkup – it will point out a number of config problems

I assume the DNS name you are using is the same as the CIFS server name or an alias ?

Yes, it is the same name. All of the workstations and servers in our environment can access it by that name with no problem. It is only those two domain controllers.

my advice

- Troubleshoot the name resolution on these two systems, DNS, nbtstat, ....

- If that doesn’t help raise an SR – between debug logs and network trace it should be possible to find out.

From the initial symptoms my guess is that the problem isn’t on the VNX side but on the client config