DCA Online Practice Questions and Answers

Correct Answer: C

Correct Answer: B

This is not how they should be distributed across three datacenters or availability zones, because having one manager in two datacenters or availability zones creates a risk of losing quorum if those datacenters or availability zones become unavailable. According to the official documentation, managers should be distributed evenly across datacenters or availability zones to ensure that the swarm can survive the loss of any one datacenter or availability zone.

Correct Answer: A

Correct Answer: A

Correct Answer: B

This set of Kubernetes tools and steps does not accomplish this, because there is no such key as .spec.containers.configMounts in the pod specification. According to the official documentation, the correct key to use for mounting a configuration file directly into a container is .spec.containers.volumeMounts, which requires a corresponding volume definition in .spec.volumes. References: https://kubernetes.io/docs/tasks/configure-pod-container/configure-pod- configmap/ #add-configmap-data-to-a-volume https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.22/#container-v1-core

Correct Answer: A

Traffic sent to the IP of this service on port 8080 will be routed to port 80 in a random pod with the label app: nginx is a correct statement about how this service routes requests. A clusterIP service is a type of service that exposes an internal IP address that is only reachable within the cluster. A clusterIP service routes requests to pods based on their labels and selectors. In this case, the service has a selector app: nginx, which means it will route requests to any pod that has the label app: nginx. The service also has a port mapping from 8080 to 80, which means it will forward requests from port 8080 on the service IP to port 80 on the pod IP. The service will use a round-robin algorithm to distribute requests among the pods that match the selector.

Correct Answer: A

This set of commands can identify the published port(s) for a container, because docker container inspect can show the port mappings for a container and docker port can list the public port that is NAT-ed to the private port. According to the official documentation, these commands can be used to find the exposed ports for a container.

Correct Answer: B

Using kubectl logs deployment api does not display the events table for this object. The kubectl logs command shows the logs of a pod or a container in a pod, but it does not show the events related to the deployment object. To see the events table for this object, you need to use kubectl describe deployment api.

Correct Answer: A

This configuration will achieve fault tolerance for managers in a swarm, because an odd number of manager nodes allows for quorum-based consensus among managers and avoids split-brain scenarios. According to the official documentation, having more than two manager nodes ensures that there is always at least one manager available in case of failures.

Correct Answer: B

This command will not mount the host's `/data' directory to the ubuntu container in read-only mode, because it has an incorrect option for making the volume read-only. According to the official documentation, the correct command should be:

docker run -v /data:/mydata:ro ubuntu

The incorrect option is:

The --mode flag does not exist and should be replaced by a :ro suffix to make the volume read-only.