Monitoring and Alerting

Overview

Monitoring systems and alerting when issues arise are critical responsibilities for system operators. Effective observability ensures that system health, performance, and security can be continuously assessed. In this unit, we will explore how to design reliable monitoring infrastructures through sound architectural decisions. We will also examine how alerts can be tuned and moderated to minimize noise, prioritize actionable events, and ensure timely response to real issues.

Learning Objectives

  1. Understand robust monitoring architecture.
  2. Understand what comprises a well architected monitoring pipeline.
  3. Understand alert fatigue and how to focus on pertinent, actionable alerts.
  4. Understand the trade off between information flow and security.
  5. Get hands on with Fail2Ban, Prometheus, and Grafana.

Relevance & Context

As environments scale and threats evolve, visibility into system activity becomes vital to security assurance. Monitoring and alerting form the backbone of incident detection and response, making them essential tools for any security engineer aiming to maintain resilience without hindering operational flow.

Prerequisites

To be successful, students should have a working understanding of skills and tools including:

  1. Basic directory navigation skills.
  2. Ability to edit and manage configuration files.
  3. Understanding of SystemD services and the use of the sysctl command.
  4. Basic knowledge of Bash scripting.

Key terms and Definitions

Tracing

Span

Label

Time Series Database (TSDB)

Queue

Upper control limit / Lower control limit (UCL/LCL)

Aggregation

SLO, SLA, SLI

Push v. Pull of data

Alerting rules

Alertmanager

Alert template

Routing

Throttling

Monitoring for defensive operations

SIEM

Intrusion Detection Systems - IDS

Intrusion Prevention Systems - IPS