Debug School: Nicholas

K8S

Nicholas — Fri, 21 Jul 2023 13:27:34 +0000

What is Kubernetes?
A CNCF product written by Google, to manage containers.

Why We need Kubernetes?
The increasing scalbility of containers could be hard to managed

How Kubernetes works?
kubuctl as clients/users, manager nodes(APIservice, controller manager, scheduler,store) to manage the workers nodes via apiservice, worker nodes(kubelet, container/docker, kubeproxy) run pods

What is Pods?
A basic managed unit of one service. Can run container(s) inside pods. The K8S will always runs the pods in desired states and numbers.

Playbook sample

Nicholas — Thu, 20 Jul 2023 13:07:04 +0000

- name: install git and wget
  hosts: web

  tasks:
  - name: Install git in ubuntu
    ansible.builtin.apt:
      name: "git"
      state: latest

  - name: Install wget in ubuntu
    ansible.builtin.apt:
      name: "wget"
      state: latest

  - name: run cmd
    ansible.builtin.cmd:ls

  - name: run bash shell
    ansible.builtin.shell: somescript.sh >> somelog.txt
    args:
      chdir: somedir/

DevOps

Nicholas — Thu, 13 Jul 2023 02:50:33 +0000

What is DevOps in simple terms? DevOps means one team act as both developers and operators.
What exactly do DevOps do? Same as what develpers and operators do. Coding, building, archieving, testing, deployment, monitor etc.
What are the list of DevOps Tools? A lot. Git,Github, Maven, Jfrog, jenkins, ansible, prometheus,grafana, docker, cloud, K8s, ELK, Terraform, Nexus,Junit, Jmeter...
How DevOps and SRE are different? DevOps is targeting to develop and deploy applications with more efficiency. SRE is more like archietecture and operator, although SRE also need coding. SRE's target is to maintain the stability of the application.
What is DevSecOps? DevOps+Security. Need to apply security compliance in every phase.