Docker DCA Online Practice Questions and Exam Preparation

Docker DCA Online Questions & Answers

• Question 91:

  A company's security policy specifies that development and production containers must run on separate nodes in a given Swarm cluster. Can this be used to schedule containers to meet the security policy requirements?

  Solution: environment variables

  A. Yes
  B. No
  B. No

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  Explanation/Reference:

  Environment variables cannot be used to schedule containers to meet the security policy requirements. Environment variables are key-value pairs that can be passed to containers when they are created or run. Environment variables can be used to configure the behavior of the containerized application or provide runtime information, such as database credentials, API keys, etc. Environment variables do not affect how containers are scheduled on nodes in a swarm mode cluster.

• Question 92:

  Will this command list all nodes in a swarm cluster from the command line?

  Solution: 'docker node Is'

  A. Yes
  B. No
  A. Yes

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  Explanation/Reference:

  Using `docker node ls' lists all nodes in a swarm cluster from the command line. The docker node command is used to manage nodes in a swarm. The docker node ls subcommand displays information about the nodes in the swarm, such as their ID, hostname, status, availability, and role.

• Question 93:

  Is this the purpose of Docker Content Trust?

  Solution: Indicate an image on Docker Hub is an official image.

  A. Yes
  B. No
  B. No

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  Explanation/Reference:

  Indicating an image on Docker Hub is an official image is not the purpose of Docker Content Trust. Official images are curated images that are provided and maintained by Docker, Inc. or by upstream software maintainers. Official images have a special badge on Docker Hub that indicates their status. Official images are not necessarily signed by Docker Content Trust, although some of them are. The purpose of Docker Content Trust is to sign and verify image tags, not to indicate official images.

• Question 94:

  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: docker logs

  A. Yes
  B. No
  B. No

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  Explanation/Reference:

  This does not configure a Docker container to export container logs to the logging Solution: The docker logs command shows information about the logs of a container. It does not export or send the logs to any external destination. To configure a Docker container to export container logs to the logging solution, you need to use the --log- driver and --log-opt flags when creating or running the container. These flags allow you to specify which logging driver and options to use for the container. For example, to use Splunk as the logging driver, you can use --log-driver splunk and provide the Splunk URL, token, and other options using --log-opt.

• Question 95:

  Will this command ensure that overlay traffic between service tasks is encrypted? Solution: docker service create --network --encrypted

  A. Yes
  B. No
  B. No

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  Explanation/Reference:

  This command will not ensure that overlay traffic between service tasks is encrypted, because it uses an invalid option for enabling encryption and an incomplete option for specifying the network. According to the official documentation, there is no such option as --encrypted for the docker service create command. The correct option to use is - -network where is an existing overlay network that was created with encryption enabled.

• Question 96:

  Will this command list all nodes in a swarm cluster from the command line?

  Solution: docker inspect nodes

  A. Yes
  B. No
  B. No

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  Explanation/Reference:

  This command does not list all nodes in a swarm cluster from the command line. The docker inspect command shows low-level information about one or more objects, such as containers, images, networks, etc. It does not show information about nodes or services. To list all nodes in a swarm cluster from the command line, you need to use docker node ls command. This command shows information about all the nodes that are part of the swarm, such as their ID, hostname, status, availability, etc.

• Question 97:

  Will this action upgrade Docker Engine CE to Docker Engine EE? Solution: Run docker engine activate.

  A. Yes
  B. No
  A. Yes

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  Explanation/Reference:

  Running docker engine activate does upgrade Docker Engine CE to Docker Engine EE. The docker engine activate command is a convenience script that automates the process of uninstalling Docker Engine CE and installing Docker Engine EE on supported platforms. It requires an activation token or license file that can be obtained from Docker Hub or Docker Store.

• Question 98:

  Which of the following are types of namespaces used by Docker to provide isolation? (Choose 2.)

  A. Host
  B. Network
  C. Process ID
  D. Authentication
  E. Storage
  B. Network
  C. Process ID

• Question 99:

  Will this configuration achieve fault tolerance for managers in a swarm? Solution: an odd number of manager nodes, totaling more than two

  A. Yes
  B. No
  A. Yes

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  Explanation/Reference:

  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.

• Question 100:

  Will this action upgrade Docker Engine CE to Docker Engine EE? Solution: Manually download the 'docker-ee' package

  A. Yes
  B. No
  A. Yes