Problem :

you can not configure http to reverse proxy for aws iot mqtt , nginx would return these error: software.amazon.awssdk.crt.mqtt.MqttException: socket is closed. at software.amazon.awssdk.crt.mqtt.MqttClientConnection.onConnectionComplete(MqttClientConnection.java:140)

Resolved :

You must use nginx module: ngx_stream_proxy_module ( like network load balancer) this is a template to resolve :

Stream{ map $ssl_preread_server_name $domain { stg-iot.yourdomain stg-iot; iot.yourdomain prod-iot; }

    upstream stg-iot {
            server IoT-xxxxxx..ap-your_region-1.amazonaws.com:443;
    }

   upstream prod-iot {
            server IoT-xxxxxx..ap-your_region-1.amazonaws.com:443;
    }
  map $ssl_server_name $targetCert {
    stg-iot.yourdomain /etc/nginx/ssl/star_yourdomain.crt;
    iot.yourdomain /etc/nginx/ssl/star_yourdomain.crt;

}

map $ssl_server_name $targetCertKey {
  stg-iot.yourdomain /etc/nginx/ssl/star_yourdomain.key;
  iot.yourdomain /etc/nginx/ssl/star_yourdomain.key;

}

    server {
            listen 443;
            ssl_certificate     $targetCert;
            ssl_certificate_key $targetCertKey;
            proxy_pass $domain;
            ssl_preread on;
    }

}

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