Backup of a share fails with Access Denied during tape change (4047426)

Date: July 2010
Affected Product & Version: NVBU
Affected Module & Version: N/A
OS Version: any

Symptoms:
Network share back ups fail when they span and change tapes. Analysis of the trace shows "Could not get handle to other process: Access Denied".


Cause:
There is a permissions issue associated with the share.

Solution 1:
If you are backing up a non-windows share, the File System Plugin user guide says "Problems might be encountered if you use this feature to backup CIFS-compatible
shares such as Samba, Snap Appliance Filers or Mac OS X Shares." The NDMP plugin should be used where appropriate.

Solution 2:
Make the NetVault User and the CIF share owner Domain Admins.

Solution 3:
Run NetVault as the user who owns the CIFs share.


Explanation:
The NetVault user does not have access rights to backup the network share. Having started all the processes necessary to write to the first tape, and having a channel open to that tape, the Plugin instigated an impersonate of a different user that has access. This works until the first tape is filled and the channel to the tape is closed.

The process with the impersonated profile no longer has permissions to connect back to NetVault to write to the second tape that has been assigned. To avoid this, the NetVault user needs access to the share without impersonating another user.