Self-Hosting an Unlimited Large File Sharing Platform: Integrating Filebrowser with Authentik Identity Management

Introduction to Enterprise-Grade Self-Hosted File Sharing

In the modern digital landscape, businesses and technical teams frequently encounter a major bottleneck: sharing exceptionally large files securely and efficiently. Traditional cloud storage providers often impose restrictive file size limits, expensive tiered pricing, or rigid data governance policies that conflict with strict compliance standards. For organizations handling massive datasets, media production assets, or sensitive corporate backups, public cloud alternatives quickly become unsustainable.

The solution lies in self-hosting. By deploying Filebrowser, an incredibly lightweight yet powerful web-based file manager, organizations can turn any server or Network Attached Storage (NAS) into an unlimited file-sharing hub. However, a file-sharing platform is only as good as its security perimeter. Exposing a file manager directly to the internet with basic, siloed authentication introduces significant vulnerabilities. This guide demonstrates how to architect a production-ready, self-hosted file-sharing platform by pairing Filebrowser with Authentik, an open-source Identity Provider (IdP), to achieve robust authentication, centralized user provisioning, and granular access control.

Why Choose Filebrowser and Authentik?

Before diving into the deployment architecture, it is essential to understand why the combination of Filebrowser and Authentik represents a superior approach for technical teams and enterprise environments.

Filebrowser: Lightweight and Fast

Unlike monolithic collaboration suites like Nextcloud or Owncloud, which bundle calendar, mail, and office suites into a heavy application stack, Filebrowser focuses entirely on one objective: efficient file management. Written in Go, it boasts an exceptionally small footprint and delivers near-native file transfer speeds. It allows users to browse directories, upload and download massive files via a slick web interface, generate secure share links, and execute shell commands if permitted. Because it mounts directly to the host's existing filesystem, there is no underlying database overhead for file indexing, ensuring compatibility with multi-terabyte storage volumes.

Authentik: Centralized Identity and Access Control

While Filebrowser includes a native user database, managing credentials separately across dozens of self-hosted internal applications creates administrative chaos and security blind spots. Authentik solves this challenge. As a versatile, open-source Identity Provider, Authentik handles Single Sign-On (SSO), Multi-Factor Authentication (MFA), user federation (such as syncing with Active Directory or LDAP), and advanced authorization policies. By routing Filebrowser traffic through Authentik, administrators can enforce strict corporate security policies, track access logs, and control exactly which teams have access to specific storage repositories.

The Architecture: How the Integration Works

To implement this solution cleanly and securely, we utilize a reverse proxy architecture. Instead of exposing the Filebrowser container directly to the public internet, all incoming traffic is routed through a reverse proxy (such as Nginx Proxy Manager, Traefik, or Caddy) combined with Authentik's forward auth middleware.

• The User Request: A user attempts to access your file-sharing domain (e.g., share.company.com).
• The Proxy Guard: The reverse proxy intercepts the request and queries Authentik to check if the user is authenticated and authorized.
• The Authentication Flow: If the user is unauthenticated, Authentik prompts them for credentials, executes MFA checks, and applies conditional access policies.
• The Handover: Once approved, Authentik passes the user's identity via HTTP headers back to the reverse proxy, which then forwards the request to Filebrowser, automatically logging the user into their corresponding workspace.

Step-by-Step Deployment Guide via Docker Compose

The most maintainable method for deploying this stack is using Docker Compose. Below is an optimized configuration file that provisions Filebrowser alongside a standard reverse proxy setup, ready to interface with an existing Authentik instance.

1. Preparing the Environment

First, establish a dedicated directory structure on your host machine to ensure data persistence and proper permission mapping:

mkdir -p /opt/filesharer/config
mkdir -p /opt/filesharer/data

2. Creating the Docker Compose File

Save the following configuration as docker-compose.yml in your deployment directory. Note that we configure Filebrowser to accept authentication headers passed from our proxy layer.

Configuration Tip: Ensure that the host storage path mapped to /data has sufficient disk space, as this is where your unlimited file-sharing repository will reside.

version: '3.8'

services:
  filebrowser:
    image: filebrowser/filebrowser:latest
    container_name: filebrowser
    user: "1000:1000"
    ports:
      - "8080:80"
    environment:
      - FB_DATABASE=/config/filebrowser.db
      - FB_CONFIG=/config/settings.json
    volumes:
      - /opt/filesharer/data:/data
      - /opt/filesharer/config:/config
    restart: unless-stopped

Configuring Authentik for Filebrowser Access

With the container infrastructure online, the next phase involves configuring Authentik to act as the gatekeeper for Filebrowser.

Step 1: Create the Provider

Log into your Authentik Admin Interface, navigate to Applications > Providers, and click Create. Select Proxy Provider as the type. This model is ideal for legacy applications or simple web services like Filebrowser that do not natively support OAuth2 or SAML protocols out of the box.

• Name: Filebrowser Provider
• Authorization flow: Select your default explicit consent or authentication flow.
• External Host: Enter the public URL of your file manager (e.g., [https://share.company.com](https://share.company.com)).

Step 2: Define the Application and Authorization Policies

Navigate to Applications > Applications and create a new application. Link it directly to the Proxy Provider you created in the previous step. Here, you can assign Policy Bindings to restrict access. For example, you can create a policy that permits access exclusively to users belonging to the "IT-Infrastructure" or "Media-Production" groups within Authentik.

Step 3: Map User Headers for Auto-Provisioning

To eliminate the need for users to log in twice, navigate to the advanced settings of your Proxy Provider. Configure Authentik to pass the authenticated user's username or email address via a specific HTTP header, such as X-Authentik-Username. In the Filebrowser configuration settings, toggle the No Auth / Reverse Proxy Auth method on, and specify X-Authentik-Username as the target header. Filebrowser will automatically trust this header, creating a seamless, friction-free SSO experience.

Optimizing for Large File Transfers and High Performance

When dealing with "unlimited" file sizes—such as 50GB video files or 100GB database dumps—standard web server configurations will fail unless properly tuned. Implement the following optimizations to guarantee stability:

1. Adjust Reverse Proxy Timeouts: Large uploads take time. Increase your proxy's proxy_read_timeout and proxy_send_timeout settings to at least 3600 seconds to prevent premature connection drops.
2. Modify Client Max Body Size: By default, Nginx limits file uploads to 1MB. In your reverse proxy configuration blocks, explicitly define client_max_body_size 0; to disable body size restrictions entirely.
3. Leverage HTTP/2 or HTTP/3: Modern HTTP protocols offer significantly improved multiplexing and stream handling, resulting in more reliable chunked uploads for large assets over high-latency networks.

Conclusion: Security and Scalability Hand-in-Hand

Integrating Filebrowser with Authentik creates a robust, self-hosted file-sharing solution that balances the freedom of unlimited cloud storage with enterprise-grade identity controls. Organizations can successfully repatriate their data from public clouds, drastically lower operational overhead, and maintain complete compliance over where corporate intellectual property resides. By investing the time to correctly implement a reverse proxy layout and granular Authentik group policies, you ensure that your high-performance file hub remains fully secure against external threats.