Replacing a Failed TrueNAS OS Drive

Overview

If your TrueNAS OS drive fails, you will need to replace it and restore your configuration to minimize downtime. This guide will walk you through the process of exporting and backing up the TrueNAS configuration, installing a new OS drive, and restoring the configuration.

Prerequisites

• A new storage device to install TrueNAS SCALE.
• A USB drive with the TrueNAS SCALE installation image.
• Access to the TrueNAS web interface (if possible) before failure.
• A backup of the TrueNAS configuration file.

Step 1: Export and Backup Configuration (Before Failure)

To ensure a smooth recovery, back up your TrueNAS configuration regularly.

Export Configuration File

1. Log in to the TrueNAS web interface.
2. Navigate to System Settings > General.
3. Scroll down to Save Configuration.
4. Click Download File and save it in a secure location.
5. (Optional) Encrypt the backup file with a strong password if it contains sensitive settings.

Backup Critical Data

• If possible, take a snapshot or backup of your TrueNAS pools to another system.
• Document any custom settings, networking configurations, and installed applications.

Step 2: Install TrueNAS on a New OS Drive

1. Prepare the Installation Media
2. Download the latest TrueNAS SCALE ISO from the official website.

3. Create a bootable USB drive using tools like Rufus (Windows) or dd (Linux/macOS).

4. Install TrueNAS on the New Drive

5. Insert the bootable USB into the server and boot from it.
6. Follow the installation wizard and select the new OS drive as the installation target.

7. Complete the installation and remove the installation media.

8. Reboot and Access TrueNAS

9. Once installed, reboot the system.
10. Access the web interface via http://<your_truenas_ip>.

Step 3: Restore Configuration

1. Log in to the new TrueNAS installation.
2. Navigate to System Settings > General.
3. Scroll down to Upload Config.
4. Click Browse, select the previously saved configuration file, and upload it.
5. TrueNAS will prompt for a reboot to apply the restored settings.
6. After reboot, verify that:
7. All storage pools are correctly imported.
8. Network settings are restored.
9. Services and applications are functioning as expected.

Step 4: Verify Storage Pools

1. Navigate to Storage > Pools.
2. Ensure that all datasets and pools are visible.
3. If pools are not automatically detected, import them manually:
4. Go to Storage > Import Pool.
5. Select the correct pool and import it.

Conclusion

By regularly backing up your TrueNAS configuration and following this guide, you can quickly recover from an OS drive failure with minimal disruption. Always maintain updated backups and test your recovery process periodically.