To manage license keys, access the admin GUI via a browser, navigate to System > Licenses.
The Licenses page will show all of the license keys installed. Each traffic manager will determine which of these keys it can use (based on platform and IP/MAC restrictions and expiry times), and select the best of these keys based on the features corresponding to each key. If the current key expires (for example, it is an evaluation key), the traffic manager will automatically select a new key and start using that. There is no need to delete old, inactive keys but it will simplify the task of managing keys.