# nginx -t
nginx: [emerg] could not build the variables_hash, you should increase either variables_hash_max_size: 512 or variables_hash_bucket_size: 64
nginx: configuration file /etc/nginx/nginx.conf test failed

add to your nginx.conf following entry

variables_hash_max_size 1024;

found here

https://forum.nginx.org/read.php?2,192277,192286#msg-192286