When you first install API Gateway, it is configured to use PBE to encrypt passwords, and has a master password of manage with an expiry interval of 90 days. You can see the current expiry date by looking at the Administration > Security > Master password screen.

The expiry interval is the time between password changes. If you do not change the master password by the expiry date, API Gateway continues to operate using the existing password indefinitely. If you specify an interval value 0, the password does not expire and no warnings are sent to API Gateway or the server log.

You must have the Manage security configurations functional privilege assigned to update the master password expiry interval.