What does systemd-repart actually do?

systemd-repart is a tool that declaratively manages partition layouts for Linux images. It can grow existing partitions and create new ones during the first boot process or when operating on an image file, and also trigger filesystem growth.

Will this replace my entire partitioning process?

For new, image-based deployments (like VMs or cloud instances), it can significantly streamline or even replace complex first-boot partition resizing scripts. It's designed for intentional, image-first workflows.

Is systemd-repart safe to use on a running system?

While it *can* operate on a running system's backing device, its primary strength and safest use case is for image-based deployments and first-boot scenarios. Always test thoroughly in a non-production environment first.

🏗️ DevOps & Infrastructure

systemd-repart: Smarter Linux Image Growth on Boot

Forget shipping fat Linux images. systemd-repart is here to revolutionize how we handle partition resizing on first boot, offering a smarter, cleaner approach for VM and cloud deployments.

Open Source Beat Apr 26, 2026 5 min read

Diagram showing a Linux image with initial partitions and then expanded partitions after systemd-repart has run.

⚡ Key Takeaways

`systemd-repart` offers a declarative, repeatable way to manage Linux partition layouts on first boot. 𝕏
It focuses on growing existing partitions and adding new ones, not shrinking or deleting. 𝕏
The `GrowFileSystem=yes` option and `x-systemd.growfs` in `/etc/fstab` work together to expand filesystems. 𝕏
Dry-running with `--dry-run=yes` against an image file is crucial for safe testing before deployment. 𝕏