Brief comparison between different abstraction, capabilities and use cases of K8s and Cloud Foundry through the eyes of a user.

1. k8s vs cf
Through the eyes of the user

2. HELLO!
Ivan Borshukov
ChaosGroup
@botu6aa

3. What is it?

4. k8s
open-source system for
automating deployment,
scaling, and management of
containerized applications
What is it?
cf
code-centric platform that
runs code in any language
or framework in the cloud
and manages its lifecycle

5. k8s
● Open-source
● Lifecycle
● Containers
What is it?
cf
● Open-source
● Lifecycle
● Applications

6. Abstractions

7. k8s
Container
Pod
Replica Set
Deployment
Daemon Set
Volume
Abstractions
cf
Application
Service

8. ● Container
● Pod - group of one or more containers with
shared storage/network
● Replication Controller - ensures that a
specified number of pod replicas are running
at any one time
● Deployment - provides declarative updates
for Pods and Replica Sets.
Kubernetes Abstractions 101

9. ● Service - defines a logical set of Pods and a
policy by which to access them
● Volume
● ConfigMap - configuration key/value pairs
● Secret - sensitive data
● Label & Label selector
● And more...
Kubernetes Abstractions 101 (continued)

10. Kubernetes Abstractions 101

11. User Interaction

12. ● CLI - both CF and k8s
● Web interface (limited functionality) - k8s
User Interaction

13. K8s
Hello, World!
$ kubectl run hello-k8s --image=hello
# or
$ kubectl apply -f descriptor.yml
# or
$ kubectl create -f descriptor.yml

14. CF
Hello, World!
$ cf push

15. Running your application
cf
● Blocks until app is
started
● Gives you logs
k8s
● Eventually starts your
containers
● You need to take care
of what’s happening

16. k8s
● Container image
● ConfigMap
● Secret
● Volume
Configuring your application
cf
● Env variables

17. k8s
● Creating a Service
○ ENV variables
○ DNS
● IaaS specific
Accessing your application
cf
● https://myapp.cfapps.i
o

18. k8s
● Direct
● Using a Service
App to App communication
cf
● https://myapp.cfapps.i
o

19. k8s
● Volumes (IaaS-specific)
● User-provided service
● Self-hosted service
Storing state
cf
● Marketplace
● User-provided service

20. Storing state

21. k8s
Viewing logs
cf
$ kubectl logs $ cf logs

22. k8s
Attaching to your Application (ssh)
cf
$ kubectl exec
$ kubectl
port-forward
$ cf ssh

23. k8s
● Labels
○ env=test
○ env=prod
○ env=prod
● Namespaces
Environment isolation
cf
● Organizations and
spaces

24. K8s Labels

25. k8s
● Global or namespace
● User-described, based
on rules
Role-based access control
cf
● Global, org or space
● Predefined roles

26. K8s roles example
rules:
- apiGroups: [""]
resources: ["pods"]
verbs: ["get", "list", "watch"]
- apiGroups: [""]
resources: ["configmaps"]
resourceNames: ["my-config"]
verbs: ["get"]

27. k8s
● Memory & CPU
● Request resources
● Limit resources
Resource restriction
cf
● Memory

28. K8s resource: request & limit
containers:
- name: frontend
image: wordpress
resources:
requests:
memory: "64Mi"
cpu: "250m"
limits:
memory: "128Mi"
cpu: "500m"

29. k8s
● Restart on crash with
backoff
● Liveness probes - is app alive
● Readiness probes - is app
ready to serve requests
● Customizable - TCP, HTTP,
custom command
Health management
cf
● Restart on crash
● Health checks - TCP, HTTP,
PID

30. Readiness & Liveness
livenessProbe:
exec:
command:
- cat
- /tmp/healthy
initialDelaySeconds: 5
periodSeconds: 2

31. Running locally

32. k8s
$ minikube start
$ minikube addons
enable efk
Attaching to your Application (ssh)
cf
$ vagrant up
$ bosh target
$ bosh deploy

33. Containers

34. k8s
● User provided
● Privileged
● Root
● Stateless or stateful
Containers
cf
● Platform-created
● Non-privileged
● Rootless
● Stateless

35. Usage Scenarios

36. k8s
● Out of the box support
● 3rd party components
integration (e.g.
Prometheus)
Application Monitoring using PULL
cf
● Different URL for each
app instance (hack)

37. Multiple processes
cf
● Multiple processes?
k8s
● Pods - group of one or
more containers with
shared storage &
network

38. ● Sidecar - extend and enhance the "main"
container
K8s Sidecar

39. ● Ambassador - proxy a local connection to the
world
K8s Ambassador

40. ● Adapter - standardize and normalize output
K8s Adapters

41. k8s
Stateful & Feature-rich

42. cf
Stateless & Simple

43. THANKS!
Any questions?

44. Credits
Special thanks to all the people who made and
released these awesome resources for free:
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