Possible reason for NGINX 499 error codes

Question

I\'m getting a lot of 499 NGINX error codes. I see that this is a client side issue. It is not a problem with NGINX or my uWSGI stack. I note the correlation in uWSGI log

Answer 1

In my case, I have setup like

AWS ELB >> ECS(nginx) >> ECS(php-fpm).

I had configured the wrong AWS security group for ECS(php-fpm) service, so Nginx wasn't able to reach out to php-fpm task container. That's why i was getting errors in nginx task log

499 0 - elb-healthchecker/2.0

Health check was configured as to check php-fpm service and confirm it's up and give back a response.