Administer App Server Agents

The following pages provide information on installing app agent, along with general information on installing AppDynamics app agents. For Agent-to-Controller version compatibility information, see Agent and Controller Compatibility.

Planning Agent Deployment

When planning your deployment, you should consider whether to install agents manually or using some form of automation. If deploying a relatively small number of agents, you may choose to install the agent manually. For larger environments involving hundreds of agents, it's likely that you would want to develop an automated deployment strategy. 

The pages in this section contain information applicable across agent types. For specific types of agents, see the following links: 

• Java: Java Agent or Install the Java Agent. 
• .NET: .NET Agent or Install the .NET Agent. 
• Node.js: Node.js Agent or Install the Node.js Agent.
• PHP: PHP Agent or Install the PHP Agent.
• Python: Python Agent or Install the Python Agent.
• Database Agent: Administer the Database Agent
• Standalone Machine Agent: Install the Standalone Machine Agent

For automated deployment guidelines, see Controller Deployment. 

App Agent Network Bandwidth Usage

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. 

1. The approximate bandwidth used by a single Java Agent with the default configuration is 5 to 8 kilobytes per second. 
2. Scaling of additional agents is linear. That is, if the average bandwidth usage for an app agent in a given deployment is 5 kilobytes, adding 10 means that bandwidth usage will be 5 × 10, or 50 kilobytes.   
3. While the average bandwidth used is 5 to 8 kbytes per second, agents send data to the Controller in bursts rather than as a steady stream of data. When testing bandwidth usage, to determine the actual kbytes per second used by an agent, you need to observe and average out traffic over the course of at least several minutes. 
4. When testing bandwidth usage in the environment, keep in mind that different types of tiers will generate a different amount of load. For instance, an app server tier that connects to a database as a remote service tends to generate more agent-to-controller traffic than one that doesn't, due to the capture and transmission of SQL information from the database.  

Agent License Considerations

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 (such as the Java or .NET agent), 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 5-minute usage data. Every hour, the 5-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.