Devices / NAS & storage / mergerfs Union filesystem

mergerfs Union filesystem firmware

current

Latest firmware: 2.42.0
Released: May 8, 2026
Category: NAS & storage
Last checked: Sep 14, 2026

How to update the mergerfs Union filesystem

Read the release notes first — self-hosted projects break config and schemas between versions more often than appliances do.
Docker: pull the new image tag and recreate the container (`docker compose pull && docker compose up -d`).
Package or bare metal: update through your distribution's package manager, or replace the binary from the releases page.
Back up the config and database directory first. For most projects a downgrade is not supported once the schema has migrated.

Always download firmware from the manufacturer or project itself. Firmwarely links out; it never hosts firmware.

What changed

# mergerfs v2.42.0 ## Donations / Sponsorship If you find mergerfs useful please consider supporting its ongoing development. https://github.com/trapexit/support ## New features * `lup` (least used percentage) policy: selects the branch with the lowest used space percentage. * `mount.mergerfs` now …

Manufacturer release notes ↗

Version history

2.42.0

May 8, 2026

FAQ

How do I update the mergerfs Union filesystem?

See the step-by-step above. Open the NAS control panel, go to the update or system section, and install the new version. Back up important data first; NAS updates can take several minutes.

How does Firmwarely know when there's a new version?

Every night we read the manufacturer's official release page for the mergerfs Union filesystem and record the version, date and changelog. If anything changed, subscribers watching this device get an email.

Is this an official mergerfs page?

No. Firmwarely is independent. Device and brand names belong to their manufacturers; always download firmware from the official source.