- Introduction to Kubernetes features - A look at Kubernetes Networking and Service Discovery - New features in Kubernetes 1.6 - Kubernetes Installation options To know more about our Kubernetes expertise, visit our center of excellence at: http://www.opcito.com/kubernetes/

1. 1
Kubernetes – Introduction and What’s new in 1.6
By Colwin Fernandes, Co-founder & CTO 27-April-2017

2. 2
Show of hands
• Plan to use containers?
• How many use containers?
• Where do you use containers?
• Development
• Staging
• Production

3. 3
Agenda
• Introduction to Kubernetes features
• A look at Kubernetes Networking and Service Discovery
• New features in Kubernetes 1.6
• Kubernetes Installation options

4. 4
Kubernetes provides orchestration for containers along with
scheduling and service discovery
• Automate the deployment and replication of containers
• Auto scaling of your containers - scale in or out containers on
the fly
• Organize containers in to groups and provide automatic load
balancing between them via Labels
• Easily roll out new versions of application containers and
redirect traffic to the new versions
• Provide container resilience, if a container dies it gets replaced
via Replication Controllers
Kubernetes - Features

5. 5
Kubernetes Architecture

6. 6
• Cluster
• Set of nodes where Kubernetes is installed. Can be baremetal or
VMs
• Pods
• Group of co-located containers representing an application
• Smallest unit that can be scheduled within Kubernetes
• Containers share the same network namespace within a Pod
• Ephemeral not permanent
• Labels
• User defined key/value tags used to attach attributes to Pods
• Used to group pods in to logical groups
• Used by Replication controllers and Services to find Pods
Kubernetes Core Concepts

7. 7
• Scheduler
• Schedules pods to run on nodes
• Global scheduler for long running jobs
• Best fit chosen based on pod requirements
• Pluggable
• Replication Controllers
• Ensure a certain number of Pods are running always
• Replaces pods that die automatically
• Can be used to scale up and down a set of labelled pods
• Services
• Defines a set of Pods and a policy to access them
• Abstraction to allow transparent handling of the ephemeral
nature of the Pods
• Provides auto load balancing over a set of labelled pods
Kubernetes Core Concepts contd -/

8. 8
Replication Controller in Action

9. 9
Replication Controller in Action

10. 10
Replication Controller in Action

11. 11
Replication Controller in Action

12. 12
Services in Action

13. 13
Services in Action

14. 14
Services in Action

15. 15
• Replica Set
• Next generation Replication Controller
• Uses different selector support – Set based
• Mainly used internally with Deployments
• Deployments
• Used to update Pods and Replica Sets
• Can create new resources or update existing resources
• Rate of update can be controlled. So, you get a rolling update
across all your containers
• Allows rolling back of updates, can stop a bad deployment
automatically
Replica Sets and Deployment Sets

16. 16
• Stateful Sets
• Provides a unique identity to pods
• Useful when you need stable network ids, persistent storage
• Ordered deployment scaling and termination
• Pod Identity persists over pod reschedules
• Daemon Sets
• Used to run a pod on all (or some) Nodes
• Primarily used to run storage, log collection or node monitoring
deamons
Stateful Sets and Daemon Sets

17. 17
• Node
• A node is a worker machine in Kubernetes
• May be a VM or physical machine
• Runs the following services
• Container Runtime (Docker, Rkt)
• Kubelet
• Kube-proxy
• Kubernetes Master
• Unified view of the cluster
• Runs API server
• Controllers like Replication, StatefulSet , ReplicaSet, DeamonSet,
Deployment live here
Kubernetes Master and Nodes(Minions)

18. 18
Docker Networking

19. 19
Docker Networking

20. 20
Docker Networking

21. 21
Docker Networking contd -/

22. 22
Docker Networking contd -/

23. 23
Kubernetes Networking

24. 24
• Kubernetes creates Docker Link compatible environment
variables in all Pods
• Containers can use the environment variable to talk to the
service endpoint
Service Discovery – Environment variables

25. 25
• The DNS server watches Kubernetes API for new Services
• The DNS server creates a set of DNS records for each Service
• Services can be resolved by the name within the same
namespace
• Pods in other namespaces can access the Service by adding the
namespace to the DNS path
• my-service.my-namespace
Service Discovery – DNS

26. 26
Kube-Proxy (iptables)

27. 27
Kube-Proxy (iptables)

28. 28
Kube-Proxy (iptables)

29. 29
Kube-Proxy (iptables)

30. 30
• Scale and Federation
• 5000 nodes (150,000 pods)
• etcd v3
• Federation for multiple clusters via kubefed
• Security
• RBAC
• Permissions can be scoped on a per name-space basis
• Control plane components
• Nodes
• Controllers
What’s new in 1.6?

31. 31
• Advanced Scheduling
• Node affinity/anti-affinity
• Taints and tolerations
• Pod affinity/anti affinity
• Multiple schedulers
• Dynamic Storage provisioning
• No need to pre-provision, create and delete on demand
• Default installation of Storage class for AWS, Azure, GCP,
OpenStack and vSphere
• Expanded range of storage, including user-written PV
provisioners
What’s new in 1.6?

32. 32
• Per pod eviction
• In case of node problems combined with tolerationSeconds, lets
users tune the duration a pod stays bound to a node that is
experiencing problems
• Pod Injection Policy
• Adds a new API resource PodPreset to inject information such as
secrets, volumes, volume mounts, and environment variables
into pods at creation time
• Custom Metrics support in the Horizontal Pod Autoscaler
What’s new in 1.6? – Alpha features

33. 33
• Kubeadm
• Ships with Kubernetes
• Assumes machines are up and running
• Integrates with your existing orchestration system
• GCE
• One click ready to use clusters
• Kops
• Fully automated installation
• Uses DNS to identify clusters
• Self-healing: everything runs in Auto-Scaling Groups
• Limited OS support (Debian preferred, Ubuntu 16.04 supported,
early support for CentOS & RHEL)
• High-Availability support
• Can directly provision, or generate terraform manifests
Kubernetes Installation

34. 34
Thank You