This article applies to:
Product edition: Phoenix
Problem description
During App Aware Backups of VMs in Druva Phoenix, the following error may appear in the job details or logs:
Required field 'username' not provided (not @optional)
Although the backup job may complete successfully, this message indicates a misconfiguration in the credential mapping for guest OS access. Left unresolved, it can hinder application-consistent backups.
Cause
This error typically occurs when the VM does not have proper credentials assigned from the Credential Store.
App Aware Backups require valid guest OS credentials to access and quiesce the application inside the VM. When these credentials are missing or improperly mapped, the backup agent throws an internal error for the missing username field—even though the backup job may technically complete.
Traceback
Follow the instructions provided in the link below to obtain job logs.
Download the job logsExtract the logs and go to Phoenix<YYYYMMDD>_<timestamp>.log file to see the below traceback in the logs
[ERROR] Error <type 'exceptions.TypeError'>: Required field "username" not provided (not @optional). Traceback -Traceback (most recent call last):File "agents/vmware/vmwareAgent.py", line 2418, in init_backupFile "agents/vmware/guest_os_utils.py", line 44, in __init__File "pyVmomi/VmomiSupport.py", line 513, in __init__File "pyVmomi/VmomiSupport.py", line 532, in __setattr__File "pyVmomi/VmomiSupport.py", line 901, in CheckFieldTypeError: Required field "username" not provided (not @optional)This traceback confirms the issue is caused by a missing or unmapped guest OS credential—specifically, the username required for app aware operations.
Resolution
To resolve the credential-related error, update the vCenter credentials from the Phoenix Management Console as described below:
Update vCenter Credentials from the Phoenix Management Console
Log in to the Phoenix Management Console.
Select the appropriate Organization.
Navigate to Protect > VMware.
Select your preferred view mode:
Grid View or
List View to see the list of registered vCenters.
If using Grid View:
Click More Options (⋮) on the vCenter card.
Select Update Credentials.
In the Update Credentials window, enter the required Username and Password.
Click Update to save changes.
If using List View:
Select the Radio Button next to the vCenter name.
Click Update Credentials from the menu bar.
In the Update Credentials window, enter the Username and Password.
Click Update to apply changes.
🔐 Note: The Username and Password should belong to a vCenter administrator account with permissions to log in to the vSphere Client.
Verification:
After updating vCenter credentials:
Re-initiate the backup for the affected VM.
Monitor the job progress and logs.
Ensure that the “Required field 'username' not provided” error no longer appears in the logs.
Additional References
To confirm the permission required for these credentials:
Prerequisites for configuring VMware virtual machines for backup | Druva | DocumentationTo assign the credentials to the Virtual Machine:
Credentials store | Druva | Documentation
Conclusion
While this error does not always imply a failed backup, addressing it is essential to ensure application-consistent data protection. Updating vCenter credentials via the management console resolves the issue and ensures seamless app aware backups. If issues persist, verify credential permissions or reach out to Druva Support for further assistance.