Error No Available Server

When accessing one of your applications, you might encounter the No Available Server error.

This error indicates that Traefik, Coolify’s proxy, is unable to route the request to your application. Typically, this occurs due to a misconfiguration in either your Traefik labels or your Cloudflare settings.

Before jumping into troubleshooting, it’s important to understand how Traefik works and routes requests to your application.

1. What is Traefik and How Does It Work?

Traefik is an open-source reverse proxy and load balancer that directs incoming requests to your applications running on Coolify.

It has four main components:

• Entrypoints: The ports where Traefik listens (usually port 80 for HTTP and 443 for HTTPS).
• Routers: They determine how requests are forwarded based on rules (such as host names).
• Middlewares: These modify requests (adding authentication, logging, or rate limiting).
• Services (Servers): Your applications that process the requests.

2. Set Up the Traefik Dashboard

The Traefik dashboard is a helpful tool for debugging issues quickly.

By default, the dashboard is disabled. Follow these steps to enable it without restarting the proxy (ensuring no downtime):

1. Add Dynamic Configuration on Coolify for Traefik

   

   • Go to your Coolify dashboard and navigate to the proxy page.
   • You will see an option to add a dynamic configuration.

2. Copy the Dashboard Dynamic Config

   Copy the dynamic configuration below and paste it into the popup on Coolify. Name the file with a .yaml extension:

   http:
     routers:
       dashboard:
         rule: 'Host(`traefik.shadow.com`) && (PathPrefix(`/`))'
         service: api@internal
         tls:
           certResolver: letsencrypt
         middlewares:
           - auth
     middlewares:
       auth:
         basicAuth:
           users:
             - '<ENTER_HASHED_USER_PASSWORD>'

   Note

   Replace the traefik.shadow.com with the domain you intend to use for accessing the dashboard.

3. Configure Authentication

   Since the Traefik dashboard does not have a built-in login page, you must add an authentication middleware to protect it.

   In the above configuration, replace <ENTER_HASHED_USER_PASSWORD> with your hashed user password (keeping the quotes). You can generate a hash using this tool.

4. Save and Access the Dashboard

   After saving the dynamic configuration, visit the domain you specified for the Traefik dashboard.

   Log in using the username and password corresponding to the hashed password you generated

3. Fix Traefik Misconfiguration

If you notice a router error on the dashboard, follow these steps:

1. Click on the router that displays the error.

   

2. In the Router details, check the error message.

   

   Error

   For me ti shows nginx-shadowx doesn't exist.

3. Open your application configuration on Coolify and review the labels.

   

   In this example, having both nginx-shadowx and nginx-shadow indicates a mismatch.

   Change them to be consistent (for example, use only nginx-shadow in both places) and then restart your application.

4. Revisit the Traefik dashboard. The router should now appear without any error messages.

   If the error persists, try accessing your application website to verify that it is functioning correctly.

4. Fix Cloudflare Misconfiguration

If your domain is being proxied through Cloudflare, ensure your TLS Encryption settings are configured correctly.

You probably be using one of the following options:

• Full (Strict) - Cloudflare expects a valid SSL certificate from your server and communicates over HTTPS.
• Full - Cloudflare does not verify the SSL certificate's validity but still communicates over HTTPS.
• Flexible - Cloudflare communicates with your server over HTTP only.

If Cloudflare is set to Full or Full (Strict) while Traefik is only listening on HTTP (port 80), Cloudflare will forward all requests to the HTTPS port.

Traefik will then be unable to find any server listening on port 443 for the given hostname (e.g., shadow.com), resulting in the No Available Server error.

Changing your TLS encryption settings in Cloudflare will resolve this issue.

Alternatively, if you prefer to use a higher encryption method on Cloudflare but Traefik is showing the error, you should configure Traefik to listen on port 443 as well.

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