Where is located the APP_KEY variable?

Hi, i’m trying to restore LibreNMS by find the APP_KEY vriable to make my graphs works, because i didn’t saved the last key and generated a new one :dotted_line_face: i got this error in ./validate.php:

[FAIL] APP_KEY does not match key used to encrypt data. APP_KEY must be the same on all nodes.
If you rotated APP_KEY, run lnms key:rotate to resolve.

So, i wanted to know if the APP_KEY variable is stored by librenms itself or by the database (I’m using Docker)
I will maybe restore all the data from yesterday