A server key is generated when you first install the server. You use this key when connecting with the client-side plugin. See the client-side Initialization section for more details.
Viewing Your Key
Using the Webmin you can find the server key in the Configuration section.
The server key is also displayed directly after installation in the console.
Regenerate A Key
In the event that you need to generate a new keyfile, log in as the coronium user and on the command line run:
sudo coronium genkey
If you regenerate the keyfile, any deployed Corona apps that use the server key will be unable to connect to the server.