Direct DevOps from Quality Thought

Authentication and Authorization in K8s Authentication answers who is making this request K8s Api server does Authentication Authorization (RBAC) Admission Control: Should this request be modified or validated who can authenticate to k8s User Service Account (Pod identity) External System Authorization There are 4 main components Role: This defines permissions inside a specific namespace Cluster-Role:… Continue reading DevOps Classroom notes 22/Feb/2026

Ansible roles Refer Here for ansible roles In ansible we can make two reusable artifacts module: To develop a reusable module, we need to write python code role (reusable playbook): A playbook can be made reusable A role cannot execute on its own, a playbook has to call it. Refer Here for changes done to… Continue reading DevOps Classroom notes 22/Feb/2026

GitOps Traditional deployment (push) Git ops deployment Gitops in k8s can be acheived using Argocd Flux Argocd when installed also installs CRDs Try Argocd with AKS Bring up aks cluster. Refer Here for argo cd installation Refer Here for core concepts prompt: Give me schema of Argocd Application and help me in writing manifest which… Continue reading DevOps Classroom notes 21/Feb/2026

Making playbook work on redhat 10 Manual steps sudo dnf update -y sudo dnf install java-21-openjdk-devel -y Rest of the steps are same the service file contents [Unit] Description=Apache Tomcat 10 After=network.target [Service] Type=forking User=tomcat Group=tomcat Environment="JAVA_HOME=/usr/lib/jvm/java-17-openjdk" Environment="CATALINA_PID=/opt/tomcat/temp/tomcat.pid" Environment="CATALINA_HOME=/opt/tomcat" Environment="CATALINA_BASE=/opt/tomcat" ExecStart=/opt/tomcat/bin/startup.sh ExecStop=/opt/tomcat/bin/shutdown.sh Restart=always [Install] WantedBy=multi-user.target Refer Here for changes done to create a new playbook… Continue reading DevOps Classroom notes 21/Feb/2026

Storing output of one command using register prompt: ansible register variable yaml – name: Example Playbook with register hosts: all tasks: – name: Check disk space ansible.builtin.command: df -h register: disk_space # The output of this task is stored in a variable named ‘disk_space’ – name: Print disk space information ansible.builtin.debug: msg: "The disk space… Continue reading DevOps Classroom notes 19/Feb/2026

Jinja2 Templates Ansible supports jinja2 templates for making files dynamic with template module configuring users.xml Refer Here for changes configuring context.xml Refer Here for changes Refer Here for service template Refer Here for creating a service file Now navigate to tomcat http://<nodeip&gt;:8080 Problem to solve: Every ansible-playbook execution is executing few tasks which ideally it… Continue reading DevOps Classroom notes 18/Feb/2026

Jinja2 Templates Ansible supports jinja2 templates for making files dynamic with template module configuring users.xml Refer Here for changes configuring context.xml Refer Here for changes Refer Here for service template Refer Here for creating a service file Now navigate to tomcat http://<nodeip&gt;:8080 Problem to solve: Every ansible-playbook execution is executing few tasks which ideally it… Continue reading DevOps Classroom notes 18/Feb/2026