Which two user accounts are created by the AppDynamies Controller during installation?

The AppDynamics Controller is a Java web application that runs on a GlassFish application server and uses a MySQL database. During the installation of the Controller, two user accounts are created by default:

The GlassFish asadmin user is the administrative user for the GlassFish server. This user has the authority to start, stop, and configure the GlassFish server and its domains. The default username for this user is admin and the default password is appdynamics. You can change the password for this user after the installation by using the asadmin command-line tool1.

The customer-specified Controller administrator account is the user account that you provide during the installation wizard. This is the account that you use to access the AppDynamics User Interface (UI) for the first time and perform various tasks such as creating applications, configuring agents, managing users and groups, and so on. You can choose any username and password for this account, but AppDynamics recommends using only ASCII characters. You can also create additional user accounts in the Controller UI after the installation2.

The other options are not user accounts that are created by the Controller installation. The Elastic search root user, the REST API user, and the MySQL appd admin user are user accounts that are used internally by the Controller components and are not exposed to the end user. The OS user that will run the controller is a user account that you need to create on the host machine before the installation, and it is not created by the Controller installation3. References: Controller Installation, Manage Users and Groups, and Update the Root User and Glassfish Admin Passwords in the AppDynamics documentation.