Effective Monitoring and Alerting

Chapter 2. Monitoring

Some benefits of monitoring are immediate, such as early detection, evidence-based decision making, and automation. But its full value extends beyond that. Monitoring plays a central role in the absorption of job knowledge and driving innovation. You can’t manage what you don’t measure. A widely deployed monitoring solution keeps everyone on the same page. Timeseries plots allow for the exchange of complex ideas that would otherwise take a thousand words. Monitoring adds great value to the system and helps to foster the culture of rapid and informed learning.

The Building Blocks

The main purpose of monitoring is to gain near real-time insight into the current state of the system, in the context of its recent performance. The extracted information helps to answer many important questions, assists in the verification of nonstandard behavior, lets you drill down for more information on an issue that has been reported, and helps you estimate the capacity of the system. Before I move on to discussing all these useful aspects, I think it will help if I discuss the fundamental building blocks of a system from the bottom up.

Data Collection

The process of monitoring starts with gathering data by collection agents, specialized software programs running on monitored entities such as hosts, databases, or network devices. Agents capture meaningful system information, encapsulate it into quantitative data inputs, and then report these data inputs to the monitoring system at ...