This talk was about how the POD looks like and why we need to use the POD concept in Kubernetes Chennai kubernetes meetup #1

1. Rahulkrishnan R A
@rahulkrishnanra
Building block of Kubernetes
Chennai Kubernetes

2. - Containers are normal process
- Process executed using two Linux kernel features
- Cgroups
- Namespace
ContainersVirtual Machines
How containers looks like?

3. Orchestration - Kubernetes
• Horizontal scaling
• Self-healing
• Automated rollouts and rollbacks
• Secret and configuration management
• Automatic Binpacking
• Batch execution

4. Pod in kubernetes
POD
PODS – grouping containers App 1
App 2
App 3

5. Kubernetes Architecture
Worker Node 1
Master Node
CLI
UI
API
Kubelet
Kube-proxy
Worker Node 2
Kubelet
Kube-proxy
Worker Node 3
Kubelet
Kube-proxy
Controller Manager
Scheduler
etcd

6. Nginx v1
Mount
Hostname
PID
Network
IPC
Nginx v2
Mount
Hostname
PID
Network
IPC
Container 1 Container 2
Isolation using namespace
Isolated Containers

8. nginx
Hostname
PID
Network
IPC
cache
localhost
Pod with multiple containers

9. How POD looks like?
Namespaces
- Net
- IPC
……
Label 1
Label 2
Label 3
Pause Container
Init Container
Post Start
Pre Stop
Main
Readiness
Liveness

10. Usecase of POD

11. How to create pod?
1) kubectl run <name> --image=<Image name> --port=<port no to be exposed>
Eg: $kubectl run nginx –image=nginx:latest –port=80
2) Using Manifest file
kubectl create – f <pod definition file path >
Eg: kubectl create –f pod.yaml
Note : Always create POD with the help of controllers

12. Manifest file

13. Demo Time

14. POD is the Building block of Kubernetes

15. @rahulkrishnanra
Thank you
https://www.meetup.com/Chennai-Kubernetes
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