The AppDynamics Rest API allows you to retrieve information and perform operations on the AppDynamics platform using HTTP requests. To retrieve all AppDynamics business applications from an AppDynamics Controller using the AppDynamics Rest API, you need to use the following URL format:

http(s)://<controller-host>:/controller/rest/applications

This URL returns the business application names and internal numeric identifiers for all the applications that are monitored by the Controller. You can use the application name or ID as a parameter for other API methods that require the application context. You can also specify the output format as XML (default) or JSON by adding the output query parameter. For example:

http(s)://<controller-host>:/controller/rest/applications?output=JSON

This URL returns the same information as the previous one, but in JSON format. You can also filter the applications by their status (alive or not) by adding the time-range-type query parameter. For example:

http(s)://<controller-host>:/controller/rest/applications?time-range-type=BEFORE_NOW&duration-in-mins=60

This URL returns only the applications that are alive in the last 60 minutes.An alive application is an application with at least one node that submits at least one metric to the Controller in the provided time range12.Reference:Application Model API,Metric and Snapshot API

The most important factor in determining sizing for AppDynamics Controller is the projected metric load per minute on the Controller. This is because the metric load represents the actual workload on the Controller, which depends on the nature of the application, the AppDynamics configuration, and the usage patterns. The number of agents, the type of agents, the number of administrators/end users, and the number of AppDynamics applications are only rough estimates that can vary greatly depending on the specific scenario. Therefore, it is recommended to test the performance of the system in a staging environment and verify the Controller sizing using the metric upload rate before deploying to production.Reference:Controller System Requirements,Performance and Controller sizing guidelines,How to Run AppDynamics in Microsoft Azure,Platform Requirements

To prepare a Linux environment for the installation of an AppDynamics Controller with a Large performance profile, which is suitable for monitoring up to 1000 agents, you need to perform the following steps:

Install libaio on the host machine if it does not already have it installed. This library facilitates asynchronous I/O operations on the system, which are required by the Controller. You can use the package manager of your Linux distribution to install libaio, such as yum or apt-get.For example, on CentOS, you can runyum install libaio1.

Verify the open file descriptor limit on the system. The file descriptor limit determines how many files a process can open at a time. The Controller requires a high file descriptor limit to handle the large number of connections and transactions. AppDynamics recommends setting the file descriptor limit to at least 65535 for the user account that runs the Controller.You can check the current file descriptor limit by runningulimit -nand modify it by editing the/etc/security/limits.conffile2.

Verify the process limit on the system. The process limit determines how many processes a user can run at a time. The Controller requires a high process limit to handle the large number of threads and subprocesses. AppDynamics recommends setting the process limit to at least 65535 for the user account that runs the Controller.You can check the current process limit by runningulimit -uand modify it by editing the/etc/security/limits.conffile2.

Other steps that are not required but recommended for the Controller installation are verifying the user account permissions, configuring the virus scanners, installing the netstat network utility, and setting the NUMA configuration2.You do not need to install MySQL or Java separately, as they are included in the Controller installation package3.Reference:Prepare Linux for the Controller,Install the Controller on Linux, andController System Requirementsin the AppDynamics documentation.

According to the Cisco AppDynamics Professional Implementer (CAPI) documents, the method to import an existing keypair to manage the Controller SSL certificate without using the Enterprise Console UI is to add the keypair to the keystore.jks using a third-party tool (A). The keystore.jks file is the default keystore for the Controller that contains the private keys and certificates for the secure communication on port 8181. If the administrator already has a custom keypair that is signed by a third-party Certificate Authority (CA) or an internal CA, they can use a third-party tool, such as KeyStore Explorer or OpenSSL, to import the keypair into the keystore.jks file. The administrator should also import the root or intermediate certificates of the CA into the cacerts.jks file, which is the default truststore for the Controller. The administrator should use the keytool utility, which is bundled with the Controller installation, to import the certificates into the cacerts.jks file.The administrator should also update the password for the keystore.jks and cacerts.jks files, and restart the Controller to apply the changes12.

The incorrect options are:

Re-run the Controller installer and specify the new keypair. (B) This is not a valid method because the Controller installer does not allow the administrator to specify a custom keypair for the Controller SSL certificate. The Controller installer only allows the administrator to specify the Controller host name, port, account name, access key, and database settings.The Controller installer does not modify the keystore.jks or cacerts.jks files, and does not import any custom keypair or certificate into the Controller keystore or truststore3.

Upload a new keystore.jks file through the Controller UI. This is not a valid method because the Controller UI does not provide any feature to upload a new keystore.jks file for the Controller SSL certificate. The Controller UI only allows the administrator to view and edit the Controller settings, such as the license, the security, the email, the analytics, and the EUM.The Controller UI does not access or modify the keystore.jks or cacerts.jks files, and does not import any custom keypair or certificate into the Controller keystore or truststore4.

Upload the keypair from within the Controller UI. (D) This is not a valid method because the Controller UI does not provide any feature to upload a custom keypair for the Controller SSL certificate. The Controller UI only allows the administrator to view and edit the Controller settings, such as the license, the security, the email, the analytics, and the EUM.The Controller UI does not access or modify the keystore.jks or cacerts.jks files, and does not import any custom keypair or certificate into the Controller keystore or truststore4.

1: Controller SSL and Certificates - AppDynamics

2: How do I resolve SSL certificate validation errors in the .NET Agent? - AppDynamics

3: Install the Controller - AppDynamics

4: Controller Settings - AppDynamics

According to the Cisco AppDynamics Professional Implementer (CAPI) documents, the two valid ways to confirm that the upgraded Java Agent is running successfully are:

Verify that the node within the Controller UI indicates the app agent is reporting. (B) This is a valid way because the Controller UI is a web-based application that allows users to monitor and manage the performance of the applications, tiers, nodes, and other entities that are instrumented by the AppDynamics agents. The Controller UI displays the status of the nodes within each tier, and indicates whether the app agent is reporting or not. If the app agent is reporting, the node icon is green and shows the agent version. If the app agent is not reporting, the node icon is gray and shows the last time the agent reported. The user can also hover over the node icon to see more details, such as the agent type, the agent version, the agent runtime directory, and the agent properties file.The user can verify that the upgraded Java Agent is running successfully by checking that the node icon is green and shows the latest agent version12.

Verify the Java Agent Version metric for that node in the Metric Browser. This is a valid way because the Metric Browser is a feature of the Controller UI that allows users to view and analyze the metrics collected by the AppDynamics agents. The Metric Browser displays the metrics in a hierarchical tree structure, where each node represents a metric category, a metric name, or a metric value. The user can expand or collapse the nodes, and select or deselect the metrics to view them in a chart. The user can also apply filters, time ranges, baselines, and other options to customize the chart. The user can verify that the upgraded Java Agent is running successfully by navigating to the Java Agent Version metric for that node in the Metric Browser. The Java Agent Version metric shows the version number of the Java Agent that is running on the node.The user can compare the metric value with the expected agent version, and check that the metric is updated after the upgrade34.

The incorrect options are:

Verify that the application log contains a message indicating success. (A) This is not a valid way because the application log does not contain any message indicating the success of the Java Agent upgrade. The application log is a file that records the events and messages that occur in the application server, such as the startup, shutdown, errors, warnings, and debug information. The application log does not record the events and messages that occur in the Java Agent, such as the installation, upgrade, configuration, or reporting. The Java Agent has its own log file, which is located in the /logs directory, and which contains the messages indicating the success or failure of the Java Agent upgrade .

Verify that the Java Agent log contains a message indicating the agent started successfully. (D) This is not a valid way because the Java Agent log does not contain any message indicating the agent started successfully after the upgrade. The Java Agent log is a file that records the events and messages that occur in the Java Agent, such as the installation, upgrade, configuration, or reporting. The Java Agent log contains a message indicating the agent started successfully when the application server is started, not when the Java Agent is upgraded. The Java Agent log does not contain any message indicating the success or failure of the Java Agent upgrade. The Java Agent log is located in the /logs directory, and the message indicating the agent started successfully is ''Agent Startup Complete'' .

1: Tiers and Nodes - AppDynamics

2: Tier Dashboard - AppDynamics

3: Metric Browser - AppDynamics

4: Java Agent Metrics - AppDynamics

[5]: Java Agent Logs - AppDynamics

[6]: Troubleshoot the Java Agent - AppDynamics