Avamar: Exchange VSS backup failing with avtar Error "Failed to create snapview, as one of the elements required for path "XXXXX.edb" not found"

The Avamar Exchange VSS backups fail with avtar error "Failed to create snapview, as one of the elements required for path "XXXXX.edb" not found"

avtar Info <7209>: Finished reading makeview input
avtar Info <7210>: Finished generating makeview tables
avtar Info <16522>: Starting copy of paths in account '/clients/XXXXXXXX' label number 3
avtar Error <7042>: Failed to create snapview, as one of the elements required for path "XXXXXXXXX.edb" not found in backup account '/XXXXXX' lablenum 3 (only found 'XXXX\E:' of path 'XXXX.edb').
avtar Info <9772>: Starting graceful (staged) termination, unable to find paths in snapview (wrap-up stage)
avtar Info <0000>: Entering the 'final' phase of termination, unable to find paths in snapview)
avtar FATAL <5155>: Backup aborted due to earlier errors.  No backup created on the server.
avtar Info <7883>: Finished at 2015-01-21 09:37:21 Eastern Standard Time, Elapsed time: 0000h:00m:01s
avtar Info <6149>: Error summary: 2 errors: 5155, 7042

This backup issue can occur in Exchange environments presenting a non-standard database configuration.
This condition is known to cause the backup failure in the Avamar product.

In this scenario, the affected database presents an inconsistent case capitalization in the database file path.
There is a mismatch between the OS "database storage path" and the Exchange Application "database location path"
 
Example of an affected database (Database4):
Paths mismatch:

• The OS path for the Databases was created with the "Mount Point" folder in upper cases (letters M and P)

H:\MountPoints\Database4\Database4.edb

• The Database4 path in the Exchange application was configured with all letters in lowercase:

H:\mountpoints\Database4\Database4.edb

Example of a non-affected database (Database2):

The OS database's path and its corresponding path within the Exchange configuration have the same case capitalization:

• Database storage path

H:\MountPoints\Database2\Database2.edb

• Database location path

H:\MountPoints\Database2\Database2.edb

To verify those paths:

• Use Windows Explorer to check the OS path
• Use the Exchange admin center (EAC) to check the database configuration
  • => servers/databases/<edit properties of the affected DB>
    • Alternatively, use the Exchange Powershell command:

Get-MailboxDatabase -Identity <affected DB name> | Select-Object edbfilepath, logfolderpath | fl

To resolve this database's case mismatch situation, the Avamar product counts with a flag called "--use-case-sensitive-paths" which takes care of these types of scenarios.

• The flag must be added in the "avexvss.cmd" file under the Avamar client var folder (default path "C:\Program Files\avs\var\") in all Exchange DAG nodes that participate in the backup process
• Also, for DAG federated backups, the flag must be added in the "avexvss.cmd" file under the Cluster client's var directory
  • This is the UNC path shared between the DAG nodes and is needed to coordinate backups and to store DAG client configuration and log files
    UNC Path Example "\\share-server\share-folder\DAGname\var\")
• The flag value must be set as "false" (its default value is "true"):

--use-case-sensitive-paths=false

 

• If the flag is only added to the proxy node (in IP-Less DAG configuration) or cluster client (in Federated configuration), the backup succeeds but the restore might fail as described in Avamar: Exchange database restore failing with avtar error stating database not found in backup
• Therefore, it is important to add the mentioned flag in every Exchange node (of the DAG cluster) participating in the backup process.

 
Setting this flag as "false" ensures that all future backups are successful.

See also Avamar: Exchange database restore failing with avtar error stating database not found in backup