[SOLVED] recv() failed (104: Connection reset by peer) while reading response header from upstream

I noticed PHP-FPM error : recv() failed (104: Connection reset by peer) while reading response header from upstream. After several times of reading frmo NGINX documentation and many other sources i found the solution.

recv() failed (104: Connection reset by peer) while reading response header from upstream

By here i want to share you how to solve the error : recv() failed (104: Connection reset by peer) while reading response header from upstream.

In other way, you simply igonre this error message while come up. The error not impact to your webserver and make it totally down. Explanation for recv() failed (104: Connection reset by peer) while reading response header from upstream, upstream: "http://127.0.0.1:9000/ :

recv() failed 
    -> nginx webserver failed

(104: Connection reset by peer) while reading response header from upstream, 
    -> no complete answer, or no answer at all

upstream: "fastcgi://127.0.0.1:9000", 
    -> who is he, who failed??? : your upstream!

from my view of point i suggest you to do :

• restart your fastcgi_process / server (PHP-FPM) : sudo systemctl restart php-fpm
• check your access-log
• enable debug-log

I have trys everal method then found a clue, that error comes up while i restarted nginx and php-fpm or that two shutting down. For resolve this we need some a couple day to check again if the error stil appear or not. In my server alll everything okay after i do restarting nginx and php-fpm.

Another cases, you may receive 502 Bad Gateway error message, upstream prematurely closed connection while reading response header from upstream.