EX280 Timed Practice Test 3 — 10 Questions

Question 1

A production Deployment using the Rolling update strategy is failing its readiness probe during a rollout, causing the update to block and eventually time out. You need to inspect the reason for the rollout failure using the OpenShift CLI without deleting the failing pods immediately. Which oc command provides the most direct diagnostic information regarding the rollout status and blockage reason?

10 minute time limit — choose an answer to begin.

Accepted Answer

oc rollout status deployment/<deployment-name>. The 'oc rollout status' command monitors the progress of a deployment and provides direct feedback on why a rollout is blocked.

Answer

oc get events --sort-by='.metadata.creationTimestamp'

Answer

oc describe deployment <deployment-name>

Answer

oc debug deployment/<deployment-name>

Question 2

An administrator needs to create a Service of type ClusterIP that exposes an application running on port 8080 inside the container, mapping it to port 80 on the Service. Which command should the administrator use?

Accepted Answer

oc expose pod frontend --port=80 --target-port=8080 --type=ClusterIP. The oc expose service or oc create service command correctly maps the targetPort inside the container to the service port using the syntax --port=80 --target-port=8080.

Answer

oc create service clusterip frontend --tcp=80:8080

Answer

oc create service clusterip frontend --port=80 --port=8080

Answer

oc expose deployment frontend --port=8080 --target-port=80

Question 3

A developer wants to track multiple versions and tags of container images within an OpenShift cluster efficiently. Which OpenShift resource provides this capability?

Accepted Answer

ImageStream. ImageStreams allow developers to combine and track multiple versions of container images through tags without needing to manage the raw registry image references directly.

Answer

Route

Answer

DeploymentConfig

Answer

BuildConfig

Question 4

Which THREE of the following mechanisms can be used to automatically trigger a new build in an OpenShift BuildConfig? (Choose three.)

Accepted Answer

ImageChange trigger. BuildConfigs support webhook triggers (GitHub, Generic), image change triggers (when a base image updates), and configuration change triggers (when the BuildConfig itself changes).

Answer

Route health-check trigger

Answer

CronJob schedule trigger

Question 5

You want to automate the application lifecycle so that every time a code change is pushed, the build and deployment occur automatically. Which combination of features should you use?

Accepted Answer

BuildConfig Webhook and ImageStream triggers. A GitHub webhook combined with ImageStream triggers creates a fully automated pipeline from code commit to deployment.

Answer

Only cron jobs

Answer

Manual build and manual rollout

Answer

DeploymentConfigs only

Question 6

An OpenShift cluster administrator needs to ensure that custom S2I builder images stored in an insecure internal registry can be successfully pulled by build pods without failing TLS verification. Where must the insecure registry be defined?

Accepted Answer

In the cluster Image resource configuration (imageregistry.config.openshift.io/cluster or image.config.openshift.io). Insecure registries must be configured in the cluster-wide Image.config.openshift.io/cluster resource (or registry configuration) so the container runtime and build machinery trust the registry.

Answer

In the OAuth client definition

Answer

In the individual BuildConfig strategy environment variables

Answer

In the Project request template metadata

Question 7

You need to perform a canary deployment by shifting traffic between two versions of your app. What is the standard way to accomplish this in OpenShift without using a Service Mesh?

Accepted Answer

Use Route weights. By adjusting the weights of the 'alternate backends' in a Route, you can control traffic splitting.

Answer

Create two separate Routes

Answer

Modify the Deployment strategy

Answer

Use the 'oc scale' command

Question 8

An administrator created a Route but external clients receive a 503 Service Unavailable error when attempting to access it. Upon checking the endpoints of the Service referenced by the Route, the administrator discovers there are zero endpoints listed. What is the most likely cause?

Accepted Answer

The Service selector labels do not match any active Pod labels.. A 503 error with zero endpoints typically indicates that the selector in the Service definition does not match the labels on any running pods.

Answer

The Route YAML has an invalid TLS certificate format.

Answer

The Ingress controller pods have crashed across all worker nodes.

Answer

The cluster DNS operator is degraded.

Question 9

An ImageStream named 'frontend' in a project contains multiple tags, including 'latest' and 'v1.0'. You want to update an existing Deployment to specifically use the 'v1.0' tag of this ImageStream. Where must this reference be updated in the Deployment specification?

Accepted Answer

In the spec.template.spec.containers[].image field pointing to image-registry.openshift-image-registry.svc:5000/namespace/frontend:v1.0.. ImageStreamTags or ImageStreamImages are referenced inside the container image field within the pod template of a Deployment.

Answer

In the spec.imageStreamRef field.

Answer

In the metadata.annotations['openshift.io/image.in-cluster'] field.

Answer

In the spec.strategy.rollingUpdate.image field.

Question 10

You want to trigger a new build automatically whenever the base image in an ImageStream changes. What must be enabled in the BuildConfig?

Accepted Answer

ImageChange trigger. An ImageChange trigger allows the BuildConfig to react to changes in a specific ImageStreamTag.

Answer

Continuous Deployment trigger

Answer

WebHook trigger

Answer

ConfigChange trigger