Slides from the GDG & BJUG meetup

1. Kubernetes & the 12 factors
cloud applications
Ana Maria Mihalceanu
#JBCNConf2019

2. @ammbra1508#GDG #BJUG
HELLO!
I am Ana
Technical Lead @ IBM
Co-founder of Bucharest Software Craftsmanship Community

3. Why 12 factors & Kubernetes?
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4. Why 12 factors & Kubernetes?
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Evolution
Declarative
formats

5. Why 12 factors & Kubernetes?
@ammbra1508#GDG #BJUG
Run at push
of a button
Evolution
Declarative
formats
Scale up
with
minimal
changes
Declarative
formats
Scale up
with
minimal
changes

6. Why 12 factors & Kubernetes?
@ammbra1508#GDG #BJUG
Portability
Run at push
of a button
Evolution
Declarative
formats
Scale up
with
minimal
changes
Clean
Contract

7. Why 12 factors & Kubernetes?
@ammbra1508#GDG #BJUG
PortabilityLocal vs
production
Run at push
of a button
Evolution
Declarative
formats
Scale up
with
minimal
changes
Clean
Contract
Continuous
deployment

8. Scenario
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9. FACTOR 1 - CODEBASE
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One codebase tracked in
revision control,
with multiple deployments.

11. FACTOR 1 - CODEBASE
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HELM
v2.x.y

12. FACTOR 2 - DEPENDENCIES
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Explicitly declare and
isolate dependencies.

13. FACTOR 3 - CONFIGURATION
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14. FACTOR 3 - CONFIGURATION
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Store configuration in the environment.
kubectl create secret docker-registry ${SECRET_NAME}
--namespace ${CLUSTER_NAMESPACE}
--docker-server=${REGISTRY}
--docker-password=${TOKEN}
--docker-username=iamapikey --docker-email=a@b.com

15. FACTOR 3 - CONFIGURATION
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Store configuration in the environment.
kubectl create secret docker-registry ${SECRET_NAME}
--namespace ${CLUSTER_NAMESPACE}
--docker-server=${REGISTRY}
--docker-password=${TOKEN}
--docker-username=iamapikey --docker-email=a@b.com

16. FACTOR 4 – BACKING SERVICE
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17. Treat backing services as attached resources.
FACTOR 4 – BACKING SERVICE
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apiVersion: v1
kind: Secret
metadata:
name: cloudant
type: Opaque
data:
binding: {}

18. FACTOR 4 – BACKING SERVICE
@ammbra1508#GDG #BJUG
Treat backing services as attached resources.
apiVersion: v1
kind: Secret
metadata:
name: cloudant
type: Opaque
data:
binding: {}

19. FACTOR 4 – BACKING SERVICE
@ammbra1508#GDG #BJUG
Treat backing services as attached resources.
apiVersion: v1
kind: Secret
metadata:
name: cloudant
type: Opaque
data:
binding: {}

20. FACTOR 5 – BUILD, RELEASE, RUN
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21. FACTOR 5 – BUILD, RELEASE, RUN
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Strictly separate build
and run stages.

22. FACTOR 5 – BUILD, RELEASE, RUN
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24. FACTOR 6 – PROCESSES
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Execute the app as one or
more stateless processes.
Container
Filesystem
Persistent
VolumeVolume

25. FACTOR 6 – PROCESSES
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kubectl apply –f ${CREATE_VOLUME}.yaml
kubectl apply –f ${COPY_SCRIPTS_POLLER}.yaml
kubectl cp ./scripts ${POD}:/${LOCATION}
kubectl apply –f ${USE_SCRIPTS}.yaml

26. FACTOR 7 – PORT BINDING
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kubectl apply –f ${FILE}

27. FACTOR 7 – PORT BINDING
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Export services via port binding.

28. FACTOR 7 – PORT BINDING
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Export services via port binding.
kubectl expose deployment/${NAME}
--type=”${SERVICE_TYPE}”
--name=${SERVICE_NAME}

29. FACTOR 8 – CONCURRENCY
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Scale out via the process model.

30. FACTOR 8 – CONCURRENCY
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kubectl autoscale deployment {$DEPLOYMENT}
--min=${MIN_PODS} --max=${MAX_PODS}
--cpu-percent=${CPU}
--namespace=${NAMESPACE}

31. FACTOR 8 – CONCURRENCY
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kubectl autoscale deployment {$DEPLOYMENT}
--min=${MIN_PODS} --max=${MAX_PODS}
--cpu-percent=${CPU}
--namespace=${NAMESPACE}
𝐝𝐞𝐬𝐢𝐫𝐞𝐝𝐑𝐞𝐩𝐥𝐢𝐜𝐚𝐬 = ceil(currentReplicas ×
currentMetricValue
𝐝𝐞𝐬𝐢𝐫𝐞𝐝𝐌𝐞𝐭𝐫𝐢𝐜𝐕𝐚𝐥𝐮𝐞
)

32. FACTOR 9 – DISPOSABILITY
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Fast startup Graceful shutdown
Maximize robustness with

33. FACTOR 9 – DISPOSABILITY
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Fast startup Graceful shutdown
Maximize robustness with
helm upgrade ${RELEASE} ${CHART} --recreate-pods

34. FACTOR 9 – DISPOSABILITY
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Application boot time

35. FACTOR 9 – DISPOSABILITY
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Rolling update one after another

37. FACTOR 10 – DEV PROD PARITY
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Time People
Tools

38. FACTOR 10 – DEV PROD PARITY
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Keep development, staging and production
as similar as possible.
kubectl create namespace ${NAMESPACE}

39. FACTOR 11 – LOGS
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40. FACTOR 11 – LOGS
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Treat logs as event streams.
kubectl create secret generic logdna-agent-key
--from-literal=logdna-agent-key=<ingestion_key>
kubectl create -f
https://repo.logdna.com/ibm/prod/logdna-agent-ds-
us-south.yaml

41. FACTOR 12 – ADMIN PROCESSES
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Run admin/management tasks as one-off processes.
kubectl create configmap ${CONFIG}
--from-file=scripts/ -o yaml
kubectl apply –f ${ONE_TIME_JOB_CONFIGURATION}

42. @ammbra1508#GDG #BJUG
TAKEAWAYS
Decouple
Decouple
infrastructure
complexity from your
application code.
Managed Services
Prefer managed
services in matters
involving
persistency.
Environment Parity
Keep your
environments as
similar as possible.

43. @ammbra1508#GDG #BJUG
TAKEAWAYS
Stateless
Design your
application as
stateless.
Scale
Your application
should be able to
process diverse
workloads.
Monitor
Use appropriate
logging in application
code and implement
cluster-level logging.

44. @ammbra1508#GDG #BJUG
The strongest factor for success is self-esteem.
Believing you can do it, believing you deserve it,
believing you will get it.
Anonymous
“ “

45. @ammbra1508#GDG #BJUG
THANKS!

46. Useful links
https://gist.github.com/ammbra/e951f8192592bc175a971a31df904c2
2
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