#StackBounty: #magento2 #magento2.3 #nginx Upstream sent too big header while reading response header from upstream

Bounty: 50

We’re running Magento 2.3.1 on AWS EC2(t2.medium) Instance with an ELB. Webserver is nginx. Sometimes, we receive the “Upstream sent too big header while reading response header from upstream.”-Error in our logs. After researching this issue, I found out that the most popular solution seems to be adjusting the fastcgi buffer size. I’ve done that without any effect.

To determine the current fastcgi response sizes, I did:

$ awk '($9 ~ /200/) { i++;sum+=$10;max=$10>max?$10:max; } END { printf("Maximum: %dnAverage: %dn",max,i?sum/i:0); }' /var/log/nginx/access.log

Maximum: 1613895
Average: 51433

Due to the huge amount of response sizes, I am not sure if the issue is nginx related. My guess is that the current buffer size rules are fine and Magento might has a bug with huge response sizes?

My current buffer sizes are:

fastcgi_pass   fastcgi_backend;
fastcgi_buffers 8 32k;


Get this bounty!!!

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