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amazon-ecsaws-fargateaws-application-load-balancer

AWS Application Load Balancer for ECS 503 errro

I have an Application load balancer configured for AWS ECS. The health check endpoint works fine and I can the 200 response but for any other endpoint the load balancer is returning this response:

<html>

<head>
    <title>503 Service Temporarily Unavailable</title>
</head>

<body>
    <center>
        <h1>503 Service Temporarily Unavailable</h1>
    </center>
</body>

</html>

All the other posts that have seen talk about health check not working as the cause of the issue but for me the health checks work perfectly find and I can see the message hitting the containers in the logs. Any idea why I am getting this error for other endpoitns?

Solution

  • Check that the traffic port and the health check port are the same.

    I can see this happening if you have the correct port configured in the health check settings, but the wrong port configured for sending actual traffic to the container.