Listen to this Post
Introduction:
The convergence of DevOps, security, and cloud-native technologies defines modern IT infrastructure. Mastering the foundational commands and practices across these domains is no longer optional but essential for building resilient, scalable, and secure systems. This article distills the core technical skills from key Linux Foundation courses into a actionable guide of verified commands and configurations.
Learning Objectives:
- Execute fundamental commands for container orchestration with Kubernetes and infrastructure automation with GitOps.
- Implement critical security controls and monitoring practices using essential cybersecurity and observability tools.
- Automate CI/CD pipelines with Jenkins and manage developer portals using Backstage-related operations.
You Should Know:
1. Kubernetes Pod and Service Management
Verified commands for interacting with a Kubernetes cluster are the bedrock of container management.
List all pods in all namespaces kubectl get pods --all-namespaces Get detailed information about a specific pod kubectl describe pod <pod-name> -n <namespace> Create a resource from a YAML file kubectl apply -f deployment.yaml Expose a deployment as a service kubectl expose deployment/my-app --port=80 --target-port=8080 --type=NodePort
Step-by-step guide:
The `kubectl` command is your primary interface for managing Kubernetes. `kubectl get` retrieves the state of resources, while `kubectl describe` provides comprehensive details crucial for troubleshooting. `kubectl apply` is the declarative way to create and update resources using YAML manifests, which should be stored in a Git repository for GitOps practices. Exposing a deployment via a service provides a stable network endpoint for your application pods.
2. GitOps with Git and Kubernetes
GitOps relies on Git as the single source of truth. These commands manage the configuration stored in Git.
Clone a repository containing your Kubernetes manifests git clone https://github.com/your-org/gitops-repo.git Add changes to the staging area git add . Commit changes with a descriptive message git commit -m "feat: Update app to version 2.1 for security patch" Push changes to the remote repository, triggering automation git push origin main View the commit history to track changes git log --oneline
Step-by-step guide:
In a GitOps workflow, every infrastructure change is made via a Git commit. After cloning your repository, you modify the YAML files (e.g., changing a container image tag). `git add` stages these changes, and `git commit` records them locally. Pushing the commit to the remote repository signals a GitOps tool like ArgoCD or Flux to automatically synchronize the live cluster state with the new configuration defined in Git, ensuring consistency and auditability.
3. Jenkins Pipeline Scripting (Declarative Pipeline)
Jenkins automates the CI/CD process. This declarative pipeline script defines a build stage.
pipeline {
agent any
stages {
stage('Build') {
steps {
sh 'mvn clean compile'
}
}
stage('Test') {
steps {
sh 'mvn test'
}
}
stage('Deploy') {
steps {
sh 'kubectl apply -f k8s-deployment.yaml'
}
}
}
}
Step-by-step guide:
This Jenkinsfile defines a pipeline with three distinct stages. The `agent any` directive tells Jenkins to allocate an executor. Each `stage` block represents a phase of the software delivery lifecycle. The `sh` step executes shell commands, in this case, using Maven to build and test a Java application, and then deploying it to Kubernetes. This pipeline should be stored in a SCM, and Jenkins is configured to detect changes, automating the entire process from code commit to deployment.
4. Essential Linux Security Hardening
Securing a Linux host is a fundamental cybersecurity task. These commands help harden the system.
Check for failed login attempts, indicating brute force attacks sudo grep "Failed password" /var/log/auth.log Update all system packages to the latest secure versions sudo apt update && sudo apt upgrade -y Check the status of the Uncomplicated Firewall (UFW) sudo ufw status verbose Enable the firewall and allow only SSH traffic sudo ufw enable sudo ufw allow ssh List all open ports and listening services sudo netstat -tuln
Step-by-step guide:
Regularly reviewing auth logs helps identify intrusion attempts. Keeping the system patched (apt upgrade) is the simplest way to mitigate known vulnerabilities. The UFW firewall is a user-friendly front-end for iptables; enabling it and default-deny all traffic except necessary services (like SSH) is a critical first step. `netstat -tuln` provides a snapshot of all network services listening for connections, allowing you to identify and close unnecessary ports.
5. OpenTelemetry Collector Configuration
OpenTelemetry provides observability. This configuration collects metrics and traces and exports them.
file: otel-collector-config.yaml receivers: otlp: protocols: grpc: endpoint: 0.0.0.0:4317 http: endpoint: 0.0.0.0:4318 processors: batch: exporters: logging: loglevel: debug prometheus: endpoint: "0.0.0.0:8889" service: pipelines: metrics: receivers: [bash] processors: [bash] exporters: [logging, prometheus] traces: receivers: [bash] processors: [bash] exporters: [bash]
Step-by-step guide:
The OpenTelemetry Collector is configured via YAML. The `receivers` section defines how data is collected (here via OTLP/gRPC and HTTP). `processors` like `batch` optimize data before export. `exporters` define the destinations; this config sends data to the logs (logging) and a Prometheus metrics endpoint. The `service` section glues everything together by defining pipelines for different telemetry signals (metrics, traces). Run the collector with ./otelcol --config=otel-collector-config.yaml.
6. Backstage Software Template Scaffolding
Backstage standardizes project creation. This template snippet defines a template for a new microservice.
Example template.yaml for a Spring Boot service
apiVersion: scaffolder.backstage.io/v1beta3
kind: Template
metadata:
name: spring-boot-service
title: Spring Boot Microservice
spec:
parameters:
- title: Fill in some info
properties:
component_id:
title: Component ID
type: string
description: Unique identifier for the component
description:
title: Description
type: string
required: [bash]
steps:
- id: template
name: Fetch Skeleton
action: fetch:template
input:
url: ./skeleton
values:
component_id: ${{ parameters.component_id }}
Step-by-step guide:
This YAML defines a software template in Backstage. The `parameters` section specifies the information a user must provide when generating a new component, such as a component_id. The `steps` section defines the actions to take; the `fetch:template` action copies a “skeleton” project structure from a source (like a directory ./skeleton) and replaces template variables with the user-provided values. This enforces best practices and accelerates project bootstrapping.
7. Windows Security Audit and Monitoring
PowerShell is key for security on Windows. These commands help audit system integrity.
Get a list of all running processes Get-Process Get the status of Windows Defender Antivirus Get-MpComputerStatus Get the last 10 security log entries (requires admin) Get-EventLog -LogName Security -Newest 10 Check for active network connections netstat -an | findstr "LISTENING"
Step-by-step guide:
PowerShell provides deep introspection into the Windows system. `Get-Process` is analogous to Linux’s `ps` and helps identify malicious software. `Get-MpComputerStatus` verifies that Windows Defender is running and up-to-date. The Security event log is critical for auditing login attempts and other security-related events. The `netstat` command, used from PowerShell, shows all listening ports, helping to identify unauthorized services.
What Undercode Say:
- Automation is the Foundation of Modern Security: The shift-left philosophy, embodied by GitOps and integrated security scanning in CI/CD pipelines, means security is no longer a final gate but a continuous, automated process. Manual checks cannot scale.
- Observability is Non-Negotiable for Resilience: You cannot secure or debug what you cannot see. OpenTelemetry provides a vendor-neutral standard to achieve true observability, which is a prerequisite for detecting sophisticated attacks and performance anomalies in complex, distributed systems.
The curated commands from these free Linux Foundation courses provide a concrete starting point. The critical analysis is that tool proficiency alone is insufficient. The greatest vulnerability often lies in the gaps between tools—the manual handoffs, the inconsistent configurations. The future lies in integrated platforms and practices like GitOps that weave security and observability directly into the fabric of the development lifecycle, making secure configurations the default, not an afterthought.
Prediction:
The abstraction of infrastructure through Kubernetes and serverless platforms will continue to accelerate, pushing security concerns further down the stack. This will lead to a greater focus on supply chain security (SBOMs, vulnerability scanning in registries) and policy-as-code (e.g., OPA, Kyverno) for automated enforcement of security guardrails. The role of the platform engineer, who curates these secure, self-service internal developer platforms (like those built with Backstage), will become central to organizational cybersecurity posture, acting as a force multiplier for entire development teams.
🎯Let’s Practice For Free:
IT/Security Reporter URL:
Reported By: Roxsross A – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
