Unable to download or access huge backup file in Plesk interface: 504 Gateway Time-out

1. Connect to the server via SSH

2. Open /etc/sw-cp-server/config file using a text editor

3. Adjust timeout limits for FastCGI to the following:

   fastcgi_read_timeout 1200
   fastcgi_send_timeout 1200

4. Open /usr/local/psa/admin/conf/php.ini file using a text editor

5. Adjust timeout limits for PHP:

   max_execution_time = 1200

6. Restart sw-engine and sw-cp-server services:

   # service sw-engine restart
   # service sw-cp-server restart

If the issue still persists increase timeout limits even greater.

Alternatively, it is possible to download the backup directly from the server via CLI bypassing Plesk interface.