Managing Application Deployments

Question 1

Tree types of probes

Answer 1

startup, readiness, liveness

Question 2

What does readiness probe determines?

Answer 2

whether or not a container is ready to serve requests

Question 3

What happens if an app fails readiness probe?

Answer 3

OpenShift removes the IP address for the container from the endpoints of all services.

Question 4

What happens container fails liveness probe?

Answer 4

OCP kills the container and tries to redeploy it

Question 5

Readiness probe config key

Answer 5

spec.containers.readinessprobe

Question 6

Liveness probe config key

Answer 6

spec.containers.livenessprobe

Question 7

Five options that control probes

Answer 7

1. initialDelaySeconds
2. timeoutSeconds
3. periodSeconds
4. successThreshold
5. failureThreshold

Question 8

Three protocols for probe execution

Answer 8

1. http
2. exec
3. tcp socket

Question 9

How do you edit deployment using the GUI

Answer 9

Edith the deployment YAML by going to Workloads → Deployment →

Question 10

Create http readiness probe using oc

Answer 10

oc set probe deployment myapp –readiness –get-url=http://:8080/healthz –period=20

Question 11

Create tcp liveness probe using oc

Answer 11

oc set probe deployment myapp –liveness –open-tcp=3306 –period=20 –timeout-seconds=1

Question 12

Get help with probe creation

Answer 12

oc set probe –help

Question 13

What is the use of DeploymentConfig?

Answer 13

Enables you to use additional features, such as

1. Custom deployment strategies
2. Lifecycle hooks (also available on Deployment)

Question 14

Two types of deployment strategies

Answer 14

1. Route based
2. Deployment config based

Question 15

Change deployment strategy with oc

Answer 15

oc patch dc/mysql –patch ‘{“spec”:{“strategy”:{“type”:”Recreate”}}}’

Question 16

Continuously run “oc get pods”

Answer 16

watch -n 2 oc get pods

Question 17

Set an env variable on a dc

Answer 17

oc set env dc/mysql HOOK_RETRIES=5

Question 18

Start a deployment

Answer 18

oc rollout latest dc/name

Question 19

view the history of deployments

Answer 19

oc rollout history dc/name

Question 20

See details of a specific deployment

Answer 20

oc rollout history dc/name –revision=1

Question 21

Retry a deployment that failed previously

Answer 21

oc rollout retry dc/name

Question 22

scale the number of pods in a deployment

Answer 22

oc scale dc/name –replicas=3

Question 23

Two types of events that trigger a deployment:

Answer 23

• Configuration change
• Image change

Question 24

Set a deployment trigger for a deployment configuration

Answer 24

oc set triggers dc/name –from-image=myproject/origin-ruby-sample:latest -c helloworld

Question 25

Deploy java app by specifying maven repo

Answer 25

oc new-app --as-deployment-config --name quip --build-env MAVEN\_MIRROR\_URL=URL https://github.com/user/app-deploy

Question 26

Activate readiness and liveness probes for an application

Answer 26

oc set probe dc/quip --liveness --readiness --get-url=http://:8080/ready --initial-delay-seconds=30 --timeout-seconds=2

Question 27

Assign an OCP internal name to an external service

Answer 27

oc create service externalname myservice --external-name myhost.example.com