In the world of data protection, there is a nightmare scenario every admin fears: an attacker gains access to your local machine, steals your cloud storage credentials, and deletes your off-site backups before launching a ransomware attack.

Even with the best encryption in the world, your data is vulnerable if the backup files themselves can be deleted.

We are excited to announce a major security enhancement to help mitigate this risk: Remote File Locking.

What is Remote File Locking?

Remote File Locking is a security feature designed to create a "digital vault" for your backup data. When enabled, Duplicati instructs the remote storage provider (such as S3 or Azure) to apply a lock to your backup volumes as they are uploaded.

Once a file is locked, it becomes immutable. This means that for a pre-defined period, the file cannot be modified or deleted—not even by the Duplicati user, and not even by someone who has managed to steal your storage API keys.

Security First: Protecting Against Malicious Loss

The primary goal of this feature is to secure your backups against accidental or malicious data loss. If a ransomware strain or a malicious actor gains access to your computer, their first move is often to find your backup configuration, grab the credentials, and wipe your cloud buckets. With Remote File Locking enabled, those deletion commands will be rejected by the storage provider. Your history remains intact, ensuring you have a "clean" point to restore from, no matter what happens to your local environment.

How It Works

Duplicati leverages the native "Object Lock" or "Retention" features of modern cloud providers. When you configure Remote File Locking:

1. Upload: Duplicati uploads a new backup volume.

2. Locking: Duplicati sends a command to the storage provider to set a "Retain Until" date on that specific file.

3. Immutability: The storage provider enforces that lock. Even if a "Delete" command is sent, the provider will keep the file until the date has passed.

This creates a "WORM" (Write Once, Read Many) environment, which is the gold standard for ransomware protection.

Getting Started

Remote File Locking requires a storage backend that supports immutability (such as Amazon S3, S3-compatible providers with Object Lock support, or Azure Blob Storage).

To learn how to configure the specific flags and retention periods for your backup sets, visit our Detailed Description Guide.

By adding this layer of defense, you can sleep a little easier knowing that even if your system is compromised, your path to recovery is locked down and safe.

Is your backup truly untouchable? Don’t wait for a security breach to find out. Head over to your Duplicati settings and enable Remote File Locking today to turn your cloud storage into a fortress. Install Duplicati now and enable remote locking on your backups.