500-430 Cisco AppDynamics Professional Implementer(CAPI) Questions and Answers

An Events Service cluster is a group of two or more Events Service nodes that work together to store and process unstructured data generated by AppDynamics components such as Application Analytics, Database Visibility, and End User Monitoring1. Using an Events Service cluster has two main advantages over a single-node instance12:

• Clusters allow data replication across multiple nodes. This means that the data is duplicated and distributed among the nodes in the cluster, providing data redundancy and protection against data loss in case of a node failure. Data replication also improves data availability and query performance, as the cluster can handle concurrent requests from multiple clients.
• Clusters are horizontally scalable by adding nodes. This means that the cluster can grow in size and capacity by adding more nodes to the cluster, without affecting the existing nodes or data. Horizontal scaling allows the cluster to handle increasing data volumes and performance demands, as well as balance the workload among the nodes. References: Events Service Deployment, What are the Benefits of Server Clustering?

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

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 run yum 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 running ulimit -n and modify it by editing the /etc/security/limits.conf file2.
• 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 running ulimit -u and modify it by editing the /etc/security/limits.conf file2.

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. References: Prepare Linux for the Controller, Install the Controller on Linux, and Controller System Requirements in the AppDynamics documentation.

According to the Cisco AppDynamics Professional Implementer (CAPI) documents, the recommended way to add capacity to the Events Service cluster is to add nodes running on machines with identical hardware matching the existing nodes12. This will increase the data storage, replication, and redundancy of the cluster, as well as the processing power for queries. The Events Service cluster is horizontally scalable, so nodes can be added as your data storage requirements grow32. The Events Service must run on dedicated machines with identical directory structures, user account profiles, and hardware profiles1. For heap space allocation, AppDynamics recommends allocating half of the available RAM to the Events Service process, with a minimum of 7 GB up to 31 GB1. Solid-state drives (SSD) can significantly outperform hard disk drives (HDD), and are therefore recommended for production deployments1.

The incorrect options are:

• Add a new Events Service cluster to share the load. (A) This is not recommended because it will create additional complexity and overhead for managing multiple clusters and routing data and queries to the appropriate cluster. It will also require more license units to enable analytics on multiple clusters.
• Add more storage to the master nodes of the cluster. © This is not recommended because it will not increase the data replication and redundancy of the cluster, nor the processing power for queries. It will also create an imbalance in the cluster, as the master nodes will have more storage than the worker nodes, which may affect the performance and stability of the cluster.
• Add more storage to as many of the existing nodes as possible. (D) This is not recommended because it will not increase the data replication and redundancy of the cluster, nor the processing power for queries. It will also create an imbalance in the cluster, as some nodes will have more storage than others, which may affect the performance and stability of the cluster.

References:

• 1: Cisco AppDynamics Professional Implementer (500-430)
• 2: Events Service Requirements - AppDynamics
• 3: Events Service Deployment - AppDynamics
• 4: Events Service Deployment - AppDynamics

To upgrade the AppDynamics Java Agent, you need to copy the existing agent directory to a backup location and replace it with the new agent directory. You also need to copy any configuration file changes made in the old directory to the new agent directory. After that, you need to restart the application JVM where the Java Agent is installed, so that the new agent can take effect. Restarting the application JVM is the only required step for the upgrade to succeed. You do not need to restart the host machine, the Machine Agent, or the AppDynamics Controller12. References: Upgrade the Java Agent, Release Upgrade Checklist for Java Agents

The Database Agent collects hardware metrics from a Windows database server using PowerShell1. PowerShell is a scripting language and a command-line shell that allows the Database Agent to execute commands and access Windows Performance Counters on the target host12. The Database Agent uses PowerShell to collect metrics such as CPU, memory, disk, and network utilization from the Windows database server1. To enable hardware monitoring for a Windows database server, the Database Agent requires the following permissions1:

• The user that runs the Database Agent must have permission to execute PowerShell scripts on the local machine.
• The user that runs the Database Agent or the Collector Service user (if using Windows Authentication) must have permission to establish a WMI connection to the target host and collect Windows Performance Counters. References: Required Monitored Host Permissions, PowerShell Overview

The user under which the JVM runs must have write privileges to the conf and logs directories in the Java Agent home. This is because the conf directory contains the agent configuration files, such as controller-info.xml and agent-config.xml, which may need to be modified or updated by the user. The logs directory contains the agent log files, such as agent.log and agent-errors.log, which are generated by the agent and may need to be accessed or rotated by the user. The user can install the agent as the same user that owns the JVM or as an administrator on the host machine. The user can restrict the remaining contents of the agent directory, such as the lib and bin directories, to read-only access12. References: Install the Java Agent, Java Agent fails to start

To install a .NET Agent patch, which is a minor update to the existing .NET Agent version, you do not need to uninstall the old agent or restart the machine. You only need to follow these steps:

• Download the .NET Agent patch from the AppDynamics Download Center.
• Launch an elevated command prompt with full administrator privileges.
• Execute the Installer.bat file from the patch archive. The batch file installs the patch and starts the AppDynamics Agent Coordinator service.
• Restart the instrumented applications, such as IIS, Windows services, or standalone applications.

References: .NET Agent and How do I deploy a .NET Agent? in the AppDynamics documentation and community.

The AppDynamics REST API for retrieving metrics allows you to get values generated for metrics by specifying the path of the metric and the time frame for the data1. The following statements are true regarding this API12:

• Metrics can be retrieved for a fixed time range. You can use the time-range-type parameter to specify a fixed time range such as BEFORE_NOW, AFTER_TIME, or BETWEEN_TIMES. You can also use the duration-in-mins parameter to specify the length of the time range in minutes.
• Wildcards can be used in the REST API metric path. You can use the asterisk () character as a wildcard to match any metric name or part of a metric name. For example, you can use the metric path Business Transaction Performance|Business Transactions||*|Average Response Time (ms) to retrieve the average response time for all business transactions in all tiers. References: Retrieve Metric Data, Retrieve Metric Hierarchy

The directory contains the EUM Server installation files, configuration files, and data files. It is recommended to back up this directory as a precaution before upgrading or migrating the EUM Server. The default location of this directory is /AppDynamics/EUM, where is the directory where you installed the Controller. You can also use the backup-eum.sh script to back up the EUM Server data12. References: Upgrade the Production EUM Server, Configure the EUM Server

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/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/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/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. References: Application Model API, Metric and Snapshot API

According to the Cisco AppDynamics Professional Implementer (CAPI) documents, the two recommendations for servers in an Events Service Cluster are:

• Should be on the same local network ©: This is a valid recommendation because the Events Service Cluster is based on Apache Cassandra, which is a distributed database that relies on network communication between the nodes. Having the servers on the same local network reduces the network latency and improves the performance and reliability of the cluster. The network bandwidth should be at least 1 Gbps, and the network firewall should allow the required ports for the Events Service Cluster12.
• Should have identical hardware specifications (D): This is a valid recommendation because the Events Service Cluster is horizontally scalable, which means that the nodes share the data storage and processing load equally. Having identical hardware specifications for the servers ensures that the cluster is balanced and efficient, and avoids performance bottlenecks or failures due to hardware differences. The hardware specifications should meet the minimum requirements for the Events Service Cluster, such as CPU cores, RAM, disk space, and disk type12.

The incorrect options are:

• Should be installed using the same user account (A): This is not a valid recommendation because the Events Service Cluster does not require the same user account for installation. The user account that is used to install the Events Service Cluster should have sudo privileges on the target hosts, but it does not have to be the same for all the hosts. The user account that is used to run the Events Service Cluster should have read and write permissions on the installation directory, but it does not have to be the same for all the hosts either12.
• Should have eight or more CPU cores (B): This is not a valid recommendation because the Events Service Cluster does not require eight or more CPU cores for the servers. The minimum requirement for the CPU cores is four, and the recommended requirement is six. Having more CPU cores may improve the performance of the cluster, but it is not a mandatory recommendation12.
• Should be running the same operating system version (E): This is not a valid recommendation because the Events Service Cluster does not require the same operating system version for the servers. The Events Service Cluster supports various Linux operating systems, such as CentOS, Red Hat, Ubuntu, and SUSE. The operating system version should be compatible with the Events Service version, but it does not have to be the same for all the hosts12.

References:

• 1: Events Service Requirements - AppDynamics
• 2: Events Service Deployment - AppDynamics