Unit 4 - Operating Running Systems

Overview

This unit concentrates on the core tasks involved in operating running systems in a Linux environment, particularly with Red Hat Enterprise Linux (RHEL). It covers:

  • Understanding resource usage CPU, memory, disk I/O.

  • Become familiar with service management frameworks.

Learning Objectives

  1. Monitor and Manage System Resources:
  • Learn to track CPU, memory, disk, and network usage.
  • Understand how to troubleshoot performance bottlenecks.

  1. Master Service and Process Control:
    Gain proficiency with systemd for managing services and understanding dependency trees.
    Acquire the ability to identify, start, stop, and restart services and processes as needed.

  2. Configure and Interpret System Logs:
    Explore journald and syslog-based logging to collect and store vital system events.
    Develop techniques to analyze log files for troubleshooting and security assessments.

  3. Implement Scheduling and Automation:
    Use cron, at, and systemd timers to automate recurring tasks.
    Understand how automated job scheduling improves reliability and reduces manual intervention.

  4. Monitor and Manage System Resources:

    • Learn to track CPU, memory, disk, and network usage using common RHEL utilities.
    • Understand best practices for troubleshooting performance bottlenecks.

  5. Master Service and Process Control:

    • Gain proficiency with systemd for managing services and understanding dependency trees.
    • Acquire the ability to identify, start, stop, and restart services and processes as needed.

  6. Configure and Interpret System Logs:

    • Explore journald and syslog-based logging to collect and store vital system events.
    • Develop techniques to analyze log files for troubleshooting and security assessments.

  7. Implement Scheduling and Automation:

    • Use cron, at, and systemd timers to automate recurring tasks.
    • Understand how automated job scheduling improves reliability and reduces manual intervention.

These objectives ensure learners can sustain, troubleshoot, and improve actively running Linux systems within enterprise environments, reducing downtime and increasing system reliability.

Relevance & Context

Operating running systems is central to any Linux administrator’s responsibilities for several reasons:

  • System Stability and Performance:
    Continuous monitoring and immediate remediation of issues ensure critical services remain available and performant.

  • Proactive Problem Resolution:
    Effective log management and automation allow administrators to detect anomalies early, schedule essential maintenance, and minimize disruptions.

  • Security and Compliance:
    Logs are often the first line of evidence in security auditing and breach investigations. Regularly reviewing and correlating logs is crucial to maintaining a secure environment.

  • Enterprise Uptime and Reliability:
    In production environments, even brief outages can lead to significant operational and financial impacts. Proper management of running systems ensures high availability and robust service delivery.

Prerequisites

Before tackling the tasks of operating running systems, learners should possess:

  • Command-Line Proficiency:
    Familiarity with fundamental shell commands, directory structures, and file management is critical to executing system operations efficiently.

  • Basic text editing skills.

  • Aware of system components.

Key Terms and Definitions

Systemd

Journalctl

Cron / At / Systemd Timers

Daemon