Mirantis Mirantis Certifications DCA Questions & Answers

• Question 51:

  What service mode is used to deploy a single task of a service to each node?

  A. replicated

  B. spread

  C. universal

  D. distributed

  E. global

  Correct Answer: E

• Question 52:

  An application image runs in multiple environments, and each environment uses different certificates and ports, what is the best practice to deploy the containers?

  A. Create a Dockerfile for each environment, specifying ports and ENV variables for certificates.

  B. Create a Dockerfile for each environment, specifying ports and Docker secrets for certificates.

  C. Create images that contain the specific configuration for every environment.

  D. Create a config file for each environment.

  Correct Answer: D

• Question 53:

  Which of the following is NOT backed up when performing a Docker Trusted backup operation?

  A. Access control to repos and images

  B. Repository metadata

  C. Image blobs

  D. DTR configurations

  Correct Answer: C

• Question 54:

  The following Docker Compose file is deployed as a stack:

  

  Is this statement correct about this health check definition?

  Solution: Health checks test for app health ten seconds apart. If the test fails, the container will be restarted three times before it gets rescheduled.

  A. Yes

  B. No

  Correct Answer: A

• Question 55:

  A users attempts to set the system time from inside a Docker container are unsuccessful. Could this be blocking this operation? Solution: Linux capabilities

  A. Yes

  B. No

  Correct Answer: A

  Linux capabilities are blocking this operation. Linux capabilities are a partitioning of the privileges traditionally associated with superuser into distinct units, known as capabilities, which can be independently enabled and disabled. Capabilities are used by Docker to restrict the operations that a container can perform on the host system. By default, Docker drops all capabilities except those needed for common operations, such as binding to ports below 1024 or mounting filesystems. One of the capabilities that is dropped by default is CAP_SYS_TIME, which allows setting the system clock. Therefore, a user cannot set the system time from inside a Docker container unless this capability is explicitly added.

• Question 56:

  During development of an application meant to be orchestrated by Kubernetes, you want to mount the /data directory on your laptop into a container.

  Will this strategy successfully accomplish this?

  Solution: Add a volume to the pod that sets hostPath.path: /data, and then mount this volume into the pod's containers as desired.

  A. Yes

  B. No

  Correct Answer: A

  Adding a volume to the pod that sets hostPath.path: /data, and then mounting this volume into the pod's containers as desired is a strategy that successfully accomplishes this. A hostPath volume mounts a file or directory from the host node's

  filesystem into a pod. It can be used to access files on the host from a container, such as configuration files, logs, binaries, etc. However, this type of volume is not portable across nodes and should be used with caution. References:

  https://kubernetes.io/docs/concepts/storage/volumes/#hostpath,

  https://kubernetes.io/docs/tasks/configure-pod-container/configure-volume-storage/

• Question 57:

  Which of the following commands will ensure that overlay traffic between service tasks is encrypted?

  A. docker service create --network --secure

  B. docker network create -d overlay --secure

  C. docker network create -d overlay -o encrypted=true

  D. docker service create --network --encrypted

  Correct Answer: C

• Question 58:

  What is the recommended way to configure the daemon flags and environment variables for your Docker daemon in a platform independent way?

  A. Set the configuration options using the ENV variable

  B. Set the configuration options in '/etc/docker/daemon.json'

  C. Set the configuration DOCKER_OPTS in '/etc/default/docker'

  D. Using 'docker config' to set the configuration options.

  Correct Answer: B

• Question 59:

  Which of the following commands is used to display system-wide Docker configuration on a host?

  A. docker info

  B. docker status

  C. docker inspect

  D. docker system

  Correct Answer: A

• Question 60:

  A Kubernetes node is allocated a /26 CIDR block (64 unique IPs) for its address space.

  If every pod on this node has exactly two containers in it, how many pods can this address space support on this node?

  A. 32

  B. 32 In every Kubernetes namespace

  C. 64 for every service routing to pods on this node

  D. 64

  Correct Answer: C