Avamar: Hyper-V RCT cluster registration fails due to the user authentication request

Summary: During the Hyper-V cluster creation, the Avamar Cluster Configuration Wizard requests the backup account credentials but does not validate them even if the Domain Admin account is used. ...

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Symptoms

Hyper-V cluster registration fails with this error in av_cluster_config_wizard.log: 

2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  Preparing to install the Avamar Hyper-V clients... 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-1' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-2' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-3' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-4' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-5' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-6' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-7' does exist 
2024-06-27 15:05:47 av_cluster_config_wizard INFO<0000>:  The 'WinClusterSvc' service on node 'Hyper-V-Node-8' does exist 
2024-06-27 15:06:24 av_cluster_config_wizard ERROR<0000>: Failed to authenticate Backup User 
2024-06-27 15:06:24 av_cluster_config_wizard ERROR<0000>: Unable to validate user credentials and updated the 'WinClusterSvc' service 
2024-06-27 15:06:24 av_cluster_config_wizard INFO<0000>:  Performing installation cleanup for federated configuration... 
.......
2024-06-27 15:06:25 av_cluster_config_wizard ERROR<0000>: Installation failed with the following error:
Failed in UserAuthentication.ValidateUser('Hyper-V-Node-1', 'WinClusterSvc') 
 

In the wizard, this message may be displayed:

Unable to validate user credentials and updated the "WinClusterSvc" service

Cause

This is due to a code issue in the Avamar Cluster Configuration tool.

The Wizard is unable to authenticate the user account credentials that are requested during the registration attempt.

Resolution

Workaround:
  1. Edit the av_cluster_config_wizard.cmd file in the local /var folder of the Hyper-V node used to configure the Avamar Hyper-V Cluster client
  2. Add the flag "--skip-authentication" (without quotes) and save the file
    (This flag instructs the Cluster Wizard to NOT prompt for user credentials before attempting to register and create the Avamar Hyper-V cluster client.)
  3. Rerun the Avamar Cluster Configuration Wizard to create the new cluster client
  4. Once the Wizard has finished, follow these steps:
    1. Go to the "Services.msc" console on the Hyper-V cluster nodes
    2. Select the "Dell Avamar Plugin Service for Windows" service and configure it to run with a domain administrator or similar account with the necessary privileges to access the Hyper-V environment. 
    3. Restart the service for the changes to take effect.

    Affected Products

    Avamar
    Article Properties
    Article Number: 000164196
    Article Type: Solution
    Last Modified: 20 Jan 2026
    Version:  7
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