Instrumenting an application adds the AppDynamics application agent (app agent) into the runtime process of the application. This page gives you an overview of installing agents in the application environment.
The Getting Started Wizard in the AppDynamics Controller walks you through the steps to download and configure an agent for your application. This section gives you an overview of how to use the wizard.
The wizard produces a fully configured agent, including a node identity. Accordingly, it is intended to be run for each application instance you want to monitor until you have the hang customizing the configuration manually.
Before installing an agent, make sure that:
After verifying the requirements, follow the workflow as guided by the wizard:
The wizard makes it easy to perform a basic installation of the agent with minimally required settings, such as the Controller host and port, SSL, application name, and tier name. For advanced options or more complicated scenarios, you need to perform a manual installation of the agent. For more information, see the agent-specific link in the following section.
For detailed installation information by agent type, see the following topics:
For automated deployment guidelines, see Controller Deployment.
The maximum length of a tier name is 100 characters and the maximum length of a node name is 225 characters for Linux and 500 characters for all other operating systems. In your tier, node and application names, you should avoid certain special characters. The characters you can use are listed on the Tiers and Nodes page.
Generally, node names should be unique. However, nodes that reside on different tiers and different machines (hosts) can have duplicate node names.
Within a business application, node names should always be unique in the following use cases:
Node names and machine names must unique. When a node is registered to a controller, it is associated with the machine it is on, and cannot be moved to another machine without changing the node name.
If the nodes names are the same in the aforementioned use cases, the nodes will not register or report successfully.
Nodes on proxy-based agents can have duplicate names on the same tier and same machine.
To rename an application, see Business Applications.
For node naming conventions by agent type, see the installation page for that agent, such as Node.js Agent or PHP Agent.
The following guidelines can help you estimate how much bandwidth overhead will be added to your environment by deploying AppDynamics agents.
Keep in mind that the exact bandwidth required for a deployment varies greatly depending on the nature of your application, the agent configuration, and the AppDynamics features you use. The best way to determine the bandwidth overhead is to test the AppDynamics deployment in a staging environment that mirrors as closely as possible the live operating environment.
For agent-based license units—including APM, database monitoring, and server monitoring—licenses are allocated to the first agents that register with the Controller up to the licensed limit. For example, with five agent licenses, the first five agents that connect to the Controller are licensed.
Agent licenses are not bound to a particular machine or application. Therefore, a transfer of an agent-based license can be done simply by shutting down the application that runs the licensed agent—uninstalling the agent if the application will need to be restarted—and starting up the new application with the newly installed agent. Once the agent disconnects, a license unit is freed for the second agent.
For application monitoring agents (Java, .NET, Node.JS, and so on), a license validation cycle runs every five minutes. It causes the agents to connect and validate that available license units are not exceeded. Historical usage data is captured during this cycle and stored as five-minute usage data. Every hour, the five-minute usage data is rolled up in hour usage data, which includes data on license unit usage. The five-minute data is purged after a few hours.