File share backup failed with Error code 1073871825

Question

Hi,

I have a 2 file shares backups running daily and after some successful completions both of them are taking about 40 minutes to 1 hour trying to complete and finally they are ending with the following info:

Error code: 1073871825

Error message: Microsoft Azure Backup encountered an internal error.

Both file shares are used for storing 2 different Containers data and the backup jobs are running when containers are down, so no activity or lock of the stored files exist.

Thanks,

Answer 1

Error code 1073871825 in Azure Backup for file shares indicates a generic internal error. It usually occurs during backup or restore operations when the Azure Backup service encounters issues with configuration, connectivity, or resource handling, even if files are not actively locked.

What This Error Means

• Internal Service Error: The code doesn’t point to a specific file lock or permission issue. Instead, it signals that the Azure Backup service itself failed to complete the operation.
• Common Scenarios:
  • Backup jobs running longer than expected (40–60 minutes) before failing.
  • Restore operations failing midway with the same error.
• Not File Locks: Even if containers are down and files are inactive, the error can still occur because it’s not related to file activity

Troubleshooting Steps

Here are recommended actions based on Microsoft’s guidance for Azure Files backup issues:

1. Check Backup Service Health
   • Verify that the Azure Backup service is healthy in your region.
   • Look for any service advisories in the Azure Service Health dashboard.
2. Validate Storage Account Configuration
   • Ensure the storage account is properly registered with the Recovery Services vault.
   • Confirm that the backup policy is correctly applied to the file shares.
3. Review Network and Connectivity
   • Check if there are intermittent connectivity issues between the vault and the storage account.
   • Ensure firewall or NSG rules aren’t blocking backup traffic.
4. Examine Job Logs
   • In the Azure portal, open the failed backup job and review detailed logs.
   • Look for warnings or secondary error codes that may provide more context.
5. Retry or Reconfigure
   • Sometimes re-running the backup after a short delay resolves transient issues.
   • If persistent, consider re-registering the file share with the vault.
6. Escalate if Needed
   • If the error continues, open a support ticket with Microsoft. Provide job logs and timestamps to help engineers trace the internal failure.

Final Takeaway:

Error 1073871825 is a generic internal error in Azure Backup. It’s not caused by file locks but by service-level issues during backup or restore. The best approach is to check configuration, logs, and service health, and escalate to Microsoft support if the problem persists