Help Center Help Articles Professional Support Professional Integrators Community RMA & Warranty Downloads Tech Specs

Troubleshooting UNAS Data Backup Issues

UNAS lets you back up your data to multiple destinations, such as another UNAS device, an SMB/CIFS server, or cloud services like Google Drive, OneDrive, Dropbox, Amazon S3, Backblaze B2, or Wasabi. This allows the 3-2-1 backup strategy for better data protection. To create a backup task, go to Drive > Settings > Backups > Create Task.

This guide helps you troubleshoot common issues when backing up data on your UNAS.

Issue 1: File conflicts during backup

  • Possible Causes: Files are being modified while the backup is running (e.g., Time Machine is active).
  • Solutions:
    • Avoid modifying files during backup.
    • Pause Time Machine or similar services before starting the backup.

Issue 2: Invalid file names for destination

  • Possible Causes: Some systems reject files with special characters (e.g., @eadir for Synology and .@__thumb for QNAP).
  • Solutions: Use the All Files view to locate and rename problematic files. Refer to the file naming guidelines for:

Issue 3: Console name change pauses backup

  • Possible Causes: Backups pause when the console name changes to prevent duplicate entries.
  • Solutions: A prompt appears to guide you to rename the backup folder.
    1. Go to your backup destination and find the folder name "UniFi Drive_[Old Console Name]":
      • UNAS or SMB/CIFS server: Your destination folder > UniFi Drive_[Old Console Name]
      • Google Drive: My Drive > UniFi Drive_[Old Console Name]
      • OneDrive: My Files > UniFi Drive_[Old Console Name]
      • Dropbox: All Files > Apps > UniFi Drive Backup > UniFi Drive_[Old Console Name]
    2. Rename the folder to "UniFi Drive_[New Console Name]/[New Console Name]_[Task Name]".
      • If the destination folder already exists with that name, change the task name in UNAS to avoid conflicts.
    3. Return to the backup task on UNAS, click Dismiss and Resume Backup.

Issue 4: Case-sensitive filename conflict

  • Possible Causes: Backups to another UNAS or CIFS/SMB server may fail if source folders contain files that differ only by letter case (e.g., test.txt vs. Test.txt). Only one of these will be backed up.
  • Solutions:
    • Rename files to eliminate case-only differences before starting the backup.
    • If a partial success message appears, locate and rename the conflicting files, and retry the backup.

Issue 5: File or folder path too long on encrypted drives

  • Possible Causes: When performing an off-site backup between two UNAS devices, backups to encrypted drives fail if file paths exceed 143 characters, due to encryption-related path length limits.
  • Solutions:
    • Shorten source folder or file names to ensure total path length stays under 143 characters.
    • Use a non-encrypted drive as the backup destination to avoid this limitation.

Issue 6: "Server Connection Failed" error during remote backup

  • Description: A "Server Connection Failed" error appears when attempting a remote backup between two UNAS devices. This means the local system couldn't connect to the remote server.
  • Possible Causes:
    • Network Unreachable: The remote UNAS is offline or unreachable.
    • VPN Not Connected: VPN or Site Magic is not active or misconfigured.
    • IP Conflict: Both local and remote UNAS devices use the same LAN subnet (e.g., 192.168.1.x), preventing VPN routing.
    • SMB Disabled: SMB service is disabled or access permissions are incorrect on the remote UNAS.
  • Solutions:
    • Check Network & VPN

      1. Ensure both UNAS devices are online and reachable.

      2. Ping the remote UNAS from the local network.

        1. Enable SSH and remember the SSH password in Site Manager > UniFi Console > Settings > Control Plane > Console > Advanced > SSH.

        2. Run the following commands on a computer connected to the UniFi Console network.

          • Replace UNIFI_GATEWAY_LAN_IP with your console's LAN IP.

          • Replace UNAS_IP with the actual IP of the device experiencing the issue.

            ssh root@UNIFI_GATEWAY_LAN_IP
            ping UNAS_IP
      3. Confirm Site Magic or VPN status shows Connected.
    • Check IP Configuration: Use different subnets for the local and remote UNAS (e.g., 192.168.1.x for local UNAS and 192.168.11.x for remote UNAS) to avoid conflicts.

    • Verify SMB Service & Permissions

      1. On the remote UNAS, ensure SMB is enabled.

      2. Confirm that remote access permissions are correctly set.

Issue 7: Console name change is not reflected in Amazon S3, Backblaze B2, or Wasabi backup tasks

  • Description: If you rename your console, the folder or object names used in Amazon S3, Backblaze B2, or Wasabi backup tasks will remain unchanged.

  • Cause: These cloud storage providers do not support renaming folders or objects after creation. As a result, the backup destination retains the original console name used at the time the task was created.

  • Result: Backup tasks will continue to run normally. This does not affect backup functionality or data integrity.

See this article for best practices on backing up UNAS data to Amazon S3, Backblaze B2, and Wasabi.

Issue 8: "Backblaze B2 transaction cap exceeded" error during remote backup

  • Description: The error "Backblaze B2 transaction cap exceeded. Please update your cap settings or try again tomorrow." occurred when setting up or running a backup task to Backblaze B2.

  • Cause: This error occurs when the total number of API transactions exceeds the 24-hour quota for your Backblaze B2 account. Backblaze enforces transaction caps to manage costs and API usage. Transactions include actions such as:

    • Connecting with your Application Key.

    • Creating or listing buckets.

    • Uploading individual files (b2_upload_file).

    • Listing files or retrieving metadata.

  • Common triggers include:

    • Frequent retries due to misconfigured permissions or incorrect bucket names.
    • Uploading a large number of small files in one backup task.
    • Multiple tasks using different Application Keys under the same account. All Application Keys share the same transaction quota across the account.
    • Running frequent automated backup tasks (e.g., hourly incremental backups).
  • Solutions:

    • Wait for the daily reset: The cap resets every 24 hours (UTC). The task will automatically retry after reset.

    • Increase the transaction cap: If you're using a paid B2 plan, go to Caps & Alerts in your Backblaze Console and adjust your Daily Transaction Cap to a higher value.

Was this article helpful?