Reverse Proxy Configuration

v0.6.7

When hosting Trailarr behind a reverse proxy (like Nginx, Apache, Caddy, Traefik, etc.), certain configurations are necessary to ensure that the application functions correctly. This includes proper routing of requests and handling of headers.

There are two common scenarios for reverse proxy setups:

1. https://trailarr.mydomain.com/ (Sub-domain)
2. https://mydomain.com/trailarr/ (Sub-directory)

Sub-domain Reverse Proxy Configuration

When hosting the application behind a reverse proxy in a sub-domain (e.g., https://trailarr.mydomain.com/), the following configurations can be used as examples.

These are example configurations for common reverse proxies, adjust them as needed for your specific setup.

Sub-directory Reverse Proxy Configuration

When hosting the application behind a reverse proxy in a sub-directory (e.g., https://mydomain.com/trailarr/), additional configuration is required to ensure proper routing and resource loading.

URL Base Setting

• Make sure to set the URL Base in the General Settings of the application to match the sub-directory path used in the reverse proxy. For example, if your application is accessible at https://mydomain.com/trailarr/, set the URL Base to /trailarr.

Example Configurations

Nginx

server {
    server_name trailarr.mydomain.com;

    location / {
        proxy_pass http://192.168.1.231:7889;

        proxy_set_header Host                $host;
        proxy_set_header X-Real-IP           $remote_addr;
        proxy_set_header X-Forwarded-For     $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto   $scheme;
        proxy_set_header X-Forwarded-Host    $host;

    }
}

server {
    server_name mydomain.com;

    location /trailarr/ {
        proxy_pass http://192.168.1.231:7889;

        proxy_set_header Host                $host;
        proxy_set_header X-Real-IP           $remote_addr;
        proxy_set_header X-Forwarded-For     $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto   $scheme;
        proxy_set_header X-Forwarded-Host    $host;
        proxy_set_header X-Forwarded-Prefix  /trailarr;
    }
}

Apache

<VirtualHost *:80>
    ServerName trailarr.mydomain.com
    ProxyPreserveHost On
    ProxyPass "/" "http://192.168.1.231:7889/"
    ProxyPassReverse "/" "http://192.168.1.231:7889/"
    RequestHeader set X-Forwarded-Proto "%{REQUEST_SCHEME}s"
    RequestHeader set X-Forwarded-Host "%{HTTP_HOST}s"
</VirtualHost>

<VirtualHost *:80>
    ServerName mydomain.com
    ProxyPreserveHost On
    ProxyPass "/trailarr/" "http://192.168.1.231:7889/"
    ProxyPassReverse "/trailarr/" "http://192.168.1.231:7889/"
    RequestHeader set X-Forwarded-Proto "%{REQUEST_SCHEME}s"
    RequestHeader set X-Forwarded-Host "%{HTTP_HOST}s"
    RequestHeader set X-Forwarded-Prefix "/trailarr"
</VirtualHost>

Caddy

trailarr.mydomain.com {
    reverse_proxy http://192.168.1.231:7889 {
        header_up X-Forwarded-Host {host}
    }
}

reverse_proxy /trailarr/* http://192.168.1.231:7889 {
    header_up X-Forwarded-Host   {host}
    header_up X-Forwarded-Prefix /trailarr
}

Traefik

http:
  routers:
    trailarr:
      rule: "Host(`trailarr.mydomain.com`)"
      service: trailarr-service
  services:
    trailarr-service:
      loadBalancer:
        servers:
          - url: "http://192.168.1.231:7889" 

http:
  routers:
    trailarr:
      rule: "PathPrefix(`/trailarr`)"
      service: trailarr-service
      middlewares:
        - strip-trailarr
        - trailarr-headers
  services:
    trailarr-service:
      loadBalancer:
        servers:
          - url: "http://192.168.1.231:7889"
  middlewares:
    strip-trailarr:
      stripPrefix:
        prefixes:
          - "/trailarr"
    trailarr-headers:
      headers:
        customRequestHeaders:
          X-Forwarded-Prefix: "/trailarr"

Additional Notes

• Forward the X-Forwarded-Prefix header from reverse proxy to Trailarr. Recommended — ensures the correct frontend is served when accessed through the proxy.
• Restart Trailarr and reverse proxy to apply the new configuration.
• After setting URL Base and restarting, Trailarr is accessible at both the local URL (http://your-ip:7889/) and the sub-directory URL (https://mydomain.com/trailarr/).

• You may need to clear your browser cache or perform a hard refresh to load the resources correctly.

  Tip

  Ctrl + Shift + I to open Developer Tools -> right-click the Refresh button -> select Empty Cache and Hard Reload

• If you encounter any issues, and want to revert back to root-only access, find the .env file in config/ folder and remove the value set for URL_BASE, then restart the application.

How It Works

When URL Base is set and Trailarr restarts, it does the following:

• Keeps the root index.html with <base href="/"> so the app remains accessible at the local IP and port (http://your-ip:7889/).
• Creates a /{url_base}/ subfolder inside the frontend build directory containing a separate index.html patched with <base href="/{url_base}/">. This makes the app also accessible at http://your-ip:7889/{url_base}/ and via the reverse proxy sub-directory URL.
• Registers a middleware that strips the /{url_base} prefix from API, WebSocket, and other server-side requests arriving without a reverse proxy (i.e., direct local access at http://your-ip:7889/{url_base}/api/...), so they are routed correctly without any proxy stripping needed.
• Reads the X-Forwarded-Prefix header (sent by the reverse proxy) to decide which index.html to serve when the proxy strips the prefix before forwarding — ensuring Angular loads with the correct base path.

Both access methods work simultaneously after a single restart — no trade-off between local and proxied access.