Avamar: Hyper-V backups fail with "Creating of snapshot failed"

Hyper-V SMB backups may fail with messages similar to the following:
 

avhypervvss Error <13806>: The wake up client status [1] is not expected. The expected status is [CREATED_VSS_SNAPSHOT]
avhypervvss Error <13799>: Remote client AVAMAR1 failed to create VSS snapshot. Status = [FAILED]
avhypervvss Error <0000>: The plugin on remote client AVAMAR1 (172.16.1.1) terminated with code 10020: completed with errors,
client log should be examined

From the AVAMAR1 client logs, we see the following messages:
 

avhypervvss Warning <19016>: Volume \\DELLEMC\IDPA_CSV1\ is not supported by Microsoft File Share Shadow Copy provider
avhypervvss Warning <40028>: The UNC path '\\DELLEMC\IDPA_CSV1\' can not be shadow copied. Make sure the 'File Server VSS Agent Service' role is enabled on the server AND the share is SMB 3.0 or higher.
avhypervvss Error <41598>: Creating of snapshot failed. No volumes were part of the snapshot.
avhypervvss Error <13846>: Unable to expand backup targets
avhypervvss Error <41674>: Failed to backup targets. Unable to snapshot targets.
avhypervvss Error <41659>: Backup did not complete successfully


 

Microsoft VSS is not able to add the SBM share volume "\\DELLEMC\IDPA_CSV1\" to the snapshot. The shadow copy is not supported in this SMB share. It is a Microsoft API (IsVolumeSupported) which is failing. 

Make sure that the following requirements for SMB file shares are adhered to:

1. If the SMB file shares are on a clustered file server for general use, then install the File Server VSS Agent Service server role on all cluster nodes. Otherwise,
backups fail when the Avamar federated cluster client is not the owner node of the virtual machines.  The Windows Hyper-V Server documentation on the Microsoft TechNet
website provides instructions to install the File Server VSS Agent Service server role.

2. Configure the permissions for each SMB file share to add full permissions for each Hyper-V Server. The  Deploy Hyper-V over SMB  article on the Microsoft
TechNet website provides instructions on how to configure the file share using either Server Manager or Windows PowerShell commands.

3. Add the Hyper-V Server to the Backup Operators group on the SMB file server: 

  a. In the Administrative Tools for the SMB file server, open the Computer Management window.
  b. Expand the Local Users and Groups node in the left pane, and select Groups.
  c. Right-click Backup Operators in the right pane, and select Properties.  The Backup Operators Properties dialog box appears.
  d. Click Add.  The Select Users, Service Accounts, or Groups dialog box appears.
  e. Click Object Types.  The Object Types dialog box appears.
  f. Select the Computers checkbox and click OK.
  g. Type the name of the Hyper-V Server and click OK.
  h. Click OK on the Backup Operators Properties dialog box.
  i. In a cluster, repeat these steps for each node.
  j. Restart the SMB server or the Server service for the changes to take effect.

4. When you configure a virtual machine to store files on the SMB file share, use only one of the following formats to specify the path to the share for each file:

• \\fileserver\fileshare\
• \\fileserver.emc.com\fileshare\
• \\10.25.10.255\fileshare\
• \\fc00-aaaa-bbbb-0000-0000-0000-0000-0001.emc.com
• \fileshare\

Do not use multiple formats for the path for the same virtual machine.  Otherwise, issues can occur during restore.

These requirements can be found in the EMC Avamar SharePoint User Guide under section "Installation -> Preparing to install the Avamar client software -> System requirement -> SMB file share requirements"