Nginx configuration check fails: the size 5242880 of shared memory zone “SSL” conflicts with already declared size 1048576

Symptoms

• Nginx configuration check fails with the error below:

  [emerg] the size 5242880 of shared memory zone "SSL" conflicts with already declared size 1048576 in /etc/nginx/plesk.conf.d/vhosts/example.com.conf

Cause

The custom ssl_session_cache configured in /etc/nginx/nginx.conf or /etc/nginx/conf.d/ssl.conf file prevents generation of the configuration file.

Resolution

1. Connect to the server via SSH

2. Edit file /etc/nginx/nginx.conf or /etc/nginx/conf.d/ssl.conf.

3. Comment the line below by changing it from:

   ssl_session_cache shared:SSL:1m;
   

   To

   #ssl_session_cache shared:SSL:1m;
   

4. Restart the Nginx service:

   # service nginx restart