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In a hybrid deployment of AppDynamics, where the AppDynamics Controller and Events Service are installed on-premises and the EUM Server is hosted in AppDynamics’ SaaS cloud, the data that is unavailable is the analytics metrics for End-User Monitoring data sets. This is because the analytics metrics require the Events Service to store and process the unstructured data generated by the EUM agents. However, in a hybrid deployment, the EUM Server and the Events Service are not connected, and the EUM Server does not send the EUM data to the Events Service. Therefore, the analytics metrics for EUM data sets, such as browser records, mobile snapshots, network requests, and custom events, are not available in the Controller UI or the Analytics UI1. The other data, such as resource loading times, session information, and browser snapshots, are available in the EUM Server UI, as they are stored and displayed by the EUM Server itself2. References: Hybrid Deployment and EUM Data Sets in the AppDynamics documentation.

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.

According to the Cisco AppDynamics Professional Implementer (CAPI) documents, the two reasons for the missing correlated server-side snapshots are:

• Server has set the HttpOnly flag on all cookies. (A) This is a valid reason because the HttpOnly flag is a security feature that prevents client-side scripts from accessing the cookies. However, the AppDynamics JavaScript Agent relies on the cookies to correlate the browser snapshots with the server-side snapshots. The JavaScript Agent injects a cookie named _appdyn_browser into the browser requests, which contains the correlation information. If the server sets the HttpOnly flag on all cookies, including the _appdyn_browser cookie, the JavaScript Agent cannot read or modify the cookie, and the correlation fails. To enable the correlation, the server should not set the HttpOnly flag on the _appdyn_browser cookie12.
• Server-side application is not instrumented with server agent. (E) This is a valid reason because the server-side snapshots are collected by the AppDynamics app agents that instrument the application servers. The app agents monitor the business transactions that are executed by the server-side application, and capture the execution context, call graphs, errors, and metrics. If the server-side application is not instrumented with the app agent, the server-side snapshots are not available, and the correlation fails. To enable the correlation, the server-side application should be instrumented with the app agent that is compatible with the application server and the Controller34.

The incorrect options are:

• Correlated server-side snapshots work only for .NET Applications. (B) This is not a valid reason because the correlated server-side snapshots work for any application server that is instrumented with the AppDynamics app agent, not only for .NET applications. The AppDynamics platform supports various application servers, such as Java, .NET, PHP, Node.js, Python, and C/C++. The app agents collect the server-side snapshots for the business transactions that are executed by the application server, regardless of the programming language or framework34.
• Correlated snapshots are visible only if the injection mechanism is Automatic. © This is not a valid reason because the correlated snapshots are visible regardless of the injection mechanism. The injection mechanism refers to the way the AppDynamics JavaScript Agent is inserted into the web pages. There are two injection mechanisms: Automatic and Manual. The Automatic injection mechanism uses the app agent to inject the JavaScript Agent into the web pages that are served by the application server. The Manual injection mechanism requires the user to manually insert the JavaScript Agent into the web pages. Both injection mechanisms support the correlation of the browser snapshots and the server-side snapshots, as long as the JavaScript Agent and the app agent are configured correctly .
• Correlated snapshots are visible only if browser is Chrome. (D) This is not a valid reason because the correlated snapshots are visible regardless of the browser. The AppDynamics JavaScript Agent supports various browsers, such as Chrome, Firefox, Safari, Edge, and Internet Explorer. The JavaScript Agent collects the browser snapshots for the web pages that are loaded by the browser, and correlates them with the server-side snapshots, regardless of the browser type or version .
• Correlated server-side snapshots are visible only if Java version is 1.7+. (F) This is not a valid reason because the correlated server-side snapshots are visible regardless of the Java version. The AppDynamics Java Agent supports various Java versions, such as 1.5, 1.6, 1.7, 1.8, and 11. The Java Agent collects the server-side snapshots for the business transactions that are executed by the Java application server, and correlates them with the browser snapshots, regardless of the Java version or vendor .

References:

• 1: Browser Snapshots - AppDynamics
• 2: Troubleshoot Browser RUM - AppDynamics
• 3: Transaction Snapshots - AppDynamics
• 4: Supported Environments and Versions - AppDynamics
• [5]: Browser Real User Monitoring - AppDynamics
• [6]: Set Up and Configure Web EUM - AppDynamics
• [7]: Browser Support - AppDynamics
• [8]: Java Agent - AppDynamics
• [9]: Java Supported Environments - AppDynamics

The Machine Agent REST API allows you to create custom events that can be used for various purposes in AppDynamics. Some of the reasons you would create custom events using this API are12:

• To create an event to track application deployment. You can use the API to send a custom event that marks the start and end of an application deployment process. This can help you monitor the impact of the deployment on the application performance and availability, as well as correlate any issues or anomalies with the deployment event.
• To create an event to be displayed along with Time Series data in a custom dashboard. You can use the API to send a custom event that contains any relevant information or context that you want to display in a custom dashboard. For example, you can send a custom event that contains the details of a configuration change, a maintenance window, a business transaction, or a user action. You can then use the custom dashboard to visualize the custom event data along with the Time Series data for the metrics you are interested in.
• To create an event to be used to trigger a health rule violation. You can use the API to send a custom event that contains a metric value that you want to use as a condition for a health rule. For example, you can send a custom event that contains the CPU utilization of a machine, and then create a health rule that evaluates the CPU utilization metric and triggers a violation if it exceeds a certain threshold. You can then use the health rule violation to generate alerts, notifications, or remediation actions. References: Machine Agent HTTP Listener, Create Custom Events