502 Bad Gateway Nginx


When I creating a new category or save product variation with features I am getting 502 bad gateway nginx error but for ex. category it is created.

MV4.12.1 , PHP7.4

Any ideas where I should look at please?


Check nginx error logs

2020-12-08 19:04:16	Error		29784#0: *249450 upstream sent too big header while reading response header from upstream				nginx error
2020-12-08 19:04:16	Error	502	POST /admin.php HTTP/2.0	https://www.xxxxxxxxx.com/admin.php?dispatch=categories.add	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36	552	nginx SSL/TLS access

Try to contact hosting administrator with this information. Looks like server should be tuned