DCA Online Practice Questions and Answers

When using the Docker client to push an image to a registry, what environment variable is used to instruct the client to perform signing of the image?

A. DOCKER_CONTENT_TRUST=1

B. DOCKER_IMAGE_SIGN=1

C. DOCKER_PUSH_SIGN=1

D. NOTARY_ENABLE=1

Does this command create a swarm service that only listens on port 53 using the UDP protocol? Solution: `docker service create -name dns-cache -p 53:53 -service udp dns-cache'

A. Yes

B. No

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

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

A container named "analytics" that stores results in a volume called "data" was created.

docker run -d --name=analytics -v data:/data app1

How are the results accessed in "data" with another container called "app2"?

A. docker run -d --name=reports --volume=data app2

B. docker run -d --name=reports --volumes-from=analytics app2

C. docker run -d --name=reports --volume=app1 app2

D. docker run -d --name=reports --mount=app1 app2

Which of the following commands will create a swarm service which only listens on port 53 using the UDP protocol?

A. docker service create --name dns-cache -p 53:53/udp dns-cache

B. docker service create --name dns-cache -p 53:53 --service udp dns-cache

C. docker service create --name dns-cache -p 53:53 ..constraint networking.protocol.udp=true dns-cache

D. docker service create --name dns-cache -p 53:53 --udp dns-cache

You want to create a container that is reachable from its host's network. Does this action accomplish this? Solution: Use --link to access the container on the bridge network.

A. Yes

B. No

Will this command mount the host's '/data' directory to the ubuntu container in read-only mode? Solution: 'docker run --add-volume /data /mydata -read-only ubuntu'

A. Yes

B. No

Your organization has a centralized logging solution, such as Splunk.

Will this configure a Docker container to export container logs to the logging solution?

Solution: Set the log-driver and log-oPt keys to values for the logging solution (Splunk) In the daemon.json

file.

A. Yes

B. No

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

Solution: inter-process communication

A. Yes

B. No

Will this command list all nodes in a swarm cluster from the command line? Solution: `docker Is -a'

A. Yes

B. No

Is this a function of UCP?

Solution: enforces the deployment of signed images to the cluster

A. Yes

B. No

In Docker Trusted Registry, how would a user prevent an image, for example 'nginx:latest' from being overwritten by another user with push access to the repository?

A. Tag the image with 'nginx:immutable'

B. Remove push access from all other users.

C. Use the DTR web UI to make the tag immutable.

D. Keep a backup copy of the image on another repository.

Two development teams in your organization use Kubernetes and want to deploy their applications while

ensuring that Kubernetes-specific resources, such as secrets, are grouped together for each application.

Is this a way to accomplish this?

Solution: Create one pod and add all the resources needed for each application

A. Yes

B. No

If installing Docker using devicemapper for storage with the Intent to run production workloads, how should devicemapper be configured

A. direct-lvm

B. loop-lvm

C. overlay-lvm

D. aufs-lvm