As we saw in Chapter 1, A Bird's-Eye View of Software Engineering, monitoring the state and performance of software systems is one of the key responsibilities associated with the role of a site reliability engineer (SRE). Before we delve deeper into the topic of monitoring and alerting, we should probably take a few minutes and clarify some of the SRE-related terms that we will be using in the following sections.
Monitoring from the perspective of a site reliability engineer
Service-level indicators (SLIs)
An SLI is a type of metric that allows us to quantify the perceived quality of a service from the perspective of the end user. Let's take a look at some common types of SLIs that can be applied to cloud-based services...
