[Dec 05, 2025] Valid DCA Test Answers Full-length Practice Certification Exams
Accurate & Verified 2025 New DCA Answers As Experienced in the Actual Test!
Docker Certified Associate (DCA) exam is designed for IT professionals who want to demonstrate their expertise in working with Docker container technology. Docker is an open-source platform for developing, deploying, and running applications in containers. The DCA exam is a certification program that validates an individual's knowledge and skills in using Docker technology. It is an industry-recognized credential that demonstrates your proficiency in managing and deploying Docker containers.
NEW QUESTION # 57
You are pulling images from a Docker Trusted Registry installation
configured to use self-signed certificates, and this error appears:
`x509: certificate signed by unknown authority.
You already downloaded the Docker Trusted Registry certificate authority certificate from https://dtr.example.com/ca.
How do you trust it? (Select two.)
- A. Place the certificate in /etc/docker/certs.d/dtr.example.com/ca.crt' on allcluster nodes.
- B. Pass '-trust-certificate ca.crt to the Docker client.
- C. Place the certificate in your OS certificate path, trust the certificate system-wide, and restart the Docker daemon across all cluster nodes.
- D. Pass -- insecure-registry to the Docker client.
- E. Place the certificate in '/etc/docker/dtr/dtr.example.com.crt' and restart theDocker daemon on all cluster nodes.
Answer: A,C
Explanation:
To trust a self-signed certificate from a Docker Trusted Registry (DTR), you need to place the certificate in the appropriate location on all cluster nodes and restart the Docker daemon. There are two possible locations for the certificate, depending on your OS and Docker version1:
* /etc/docker/certs.d/dtr.example.com/ca.crt: This is the preferred location for Linux systems and Docker versions 1.13 and higher. This directory is scanned by Docker for certificates and keys for each registry domain2.
* Your OS certificate path: This is the fallback location for other OSes and Docker versions. You need to find the certificate store for your OS and copy the certificate there. You also need to trust the certificate system-wide, which may require additional steps depending on your OS3.
The other options are not correct because:
* Passing '-trust-certificate ca.crt to the Docker client is not a valid option. There is no such flag for the Docker client4.
* Placing the certificate in '/etc/docker/dtr/dtr.example.com.crt' is not a valid location. The certificate should be in the /etc/docker/certs.d directory, not the /etc/docker/dtr directory1.
* Passing - insecure-registry to the Docker client is not a recommended option. This flag disables the TLS verification for the registry, which makes the communication insecure and vulnerable to attacks.
Reference:
* Use self-signed certificates | Docker Docs
* Test an insecure registry | Docker Docs
* Add TLS certificates as a trusted root authority to the host OS | Docker Docs
* docker | Docker Docs
* [Deploy a registry server | Docker Docs]
NEW QUESTION # 58
Seven managers are in a swarm cluster.
Is this how should they be distributed across three datacenters or availability zones?
Solution: 3-2-2
- A. Yes
- B. No
Answer: A
NEW QUESTION # 59
Which statement is correct about cluster management in Docker Enterprise Edition 3.x?
- A. Clusters can contain Linux and Windows Server 2008 R2 only.
- B. Clusters can contain Linux, Windows Server 2016 and 2019, and Linux on IBM z Systems.
- C. Clusters can contain Windows 10 and Windows Server 2016 only.
- D. Clusters can contain Linux only.
Answer: B
NEW QUESTION # 60
You are troubleshooting a Kubernetes deployment called api, and want to see the events table for this object.
Does this command display it?
Solution: kubectl logs deployment api
- A. Yes
- B. No
Answer: B
Explanation:
= The command kubectl logs deployment api does not display the events table for the deployment object, but rather the logs of the pods that belong to the deployment. To see the events table, you need to use the command kubectl describe deployment api, which shows the details of the deployment, including the events1. References: Kubernetes Documentation, Practice Questions for Docker Certified Associate (DCA) Exam
NEW QUESTION # 61
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. NOTARY_ENABLE=1
Correct - B. DOCKER_PUSH_SIGN=1
- C. DOCKER_IMAGE_SIGN=1
- D. DOCKER_CONTENT_TRUST=1
Answer: D
NEW QUESTION # 62
During development of an application meant to be orchestrated by Kubemetes, you want to mount the /data directory on your laptop into a container.
Will this strategy successfully accomplish this?
Solution. Create a Persistent VolumeClaim requesting storageClass:"" (which defaults to local storage) and hostPath: /data, and use this to populate a volume in a pod.
- A. Yes
- B. No
Answer: B
Explanation:
= This strategy will not successfully accomplish this. A PersistentVolumeClaim (PVC) is a request for storage by a user that is automatically bound to a suitable PersistentVolume (PV) by Kubernetes1. A PV is a piece of storage in the cluster that has been provisioned by an administrator or dynamically provisioned using StorageClasses1. A hostPath is a type of volume that mounts a file or directory from the host node's filesystem into a pod2. It is mainly used for development and testing on a single-node cluster, and not recommended for production use2.
The problem with this strategy is that it assumes that the hostPath /data on the node is the same as the /data directory on your laptop. This is not necessarily true, as the node may be a different machine than your laptop, or it may have a different filesystem layout. Also, the hostPath volume is not portable across nodes, so if your pod is scheduled on a different node, it will not have access to the same /data directory2. Furthermore,the storageClass parameter is not applicable for hostPath volumes, as they are not dynamically provisioned3.
To mount the /data directory on your laptop into a container, you need to use a different type of volume that supports remote access, such as NFS, Ceph, or GlusterFS4. You also need to make sure that your laptop is accessible from the cluster network and that it has the appropriate permissions to share the /data directory. Alternatively, you can usea tool like Skaffold or Telepresence to sync your local files with your cluster56. Reference:
Persistent Volumes | Kubernetes
Volumes | Kubernetes
Storage Classes | Kubernetes
Kubernetes Storage Options | Kubernetes Academy
Skaffold | Easy and Repeatable Kubernetes Development
Telepresence: fast, local development for Kubernetes and OpenShift microservices
NEW QUESTION # 63
Is this statement correct?
Solution.A Dockerfile stores persistent data between deployments of a container
- A. Yes
- B. No
Answer: B
Explanation:
Explanation
= A Dockerfile does not store persistent data between deployments of a container. A Dockerfile is a text document that contains instructions for building a Docker image. A Docker image is a read-only template that defines the layers and configuration of a container. A Docker container is an isolated and ephemeral instance of a Docker image that runs on the Docker Engine. Docker containers are not meant to store persistent data, as any changes made to the container's filesystem are lost when the container is removed. To store persistent data between deployments of a container, you need to use volumes or bind mounts. Volumes and bind mounts are ways to attach external storage to a container, so that the data is preserved even if the container is deleted.
Volumes are managed by Docker and stored in a location on the host system that is independent of the container's lifecycle. Bind mounts are files or directories on the host system that are mounted into a container. References:
* Persist container data
* Dockerfile reference
* Docker MySQL Persistence
* Persist the DB
* Docker - Dockerfile, persist data with VOLUME
NEW QUESTION # 64
Will this command list all nodes in a swarm cluster from the command line?
Solution: 'docker swarm nodes'
- A. Yes
- B. No
Answer: B
NEW QUESTION # 65
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
Answer: B
NEW QUESTION # 66
Will a DTR security scan detect this?
Solution. private keys copied to the image
- A. Yes
- B. No
Answer: B
Explanation:
Explanation
A DTR security scan does not detect private keys copied to the image. A DTR security scan is a feature that scans images for known vulnerabilities in the software packages or dependencies that are installed in the image. A DTR security scan does not check for private keys or other sensitive data that may be accidentally or intentionally copied to the image. To avoid copying private keys to the image, you should use Docker secrets or other secure mechanisms to manage your credentials. References:
https://docs.docker.com/ee/dtr/user/manage-images/scan-images-for-vulnerabilities/,
https://docs.docker.com/engine/swarm/secrets/
NEW QUESTION # 67
Is this a function of UCP?
Solution: enforces the deployment of signed images to the cluster
- A. Yes
- B. No
Answer: A
Explanation:
= This is a function of UCP, as it integrates with Docker Trusted Registry (DTR) to provide built-in security and access control for your images. DTR allows you to enforce security policies and only allow running applications that use Docker images you know and trust. You can sign your images with Docker Content Trust (DCT) to prove their authenticity and integrity. UCP will verify the signatures of the images before deploying them to the cluster12. Reference:
Universal Control Plane overview | dockerlabs
How to Sign Your Docker Images to Increase Trust - How-To Geek
NEW QUESTION # 68
Will this command mount the host's '/data1 directory to the ubuntu container in read-only mode?
Solution. 'docker run -v /data:/mydata -mode readonly ubuntu'
- A. Yes
- B. No
Answer: B
Explanation:
Explanation
This command does not mount the host's /data directory to the ubuntu container in read-only mode. The -v or
--volume flag mounts a host directory or a named volume to a container. The syntax for mounting a host directory is -v <host-path>:<container-path>[:<options>]. The options can be ro for read-only mode, rw for read-write mode, z or Z for SELinux labels, etc. In this command, -mode readonly is not a valid option and will cause an error. To mount the host's /data directory to the ubuntu container in read-only mode, you need to use -v /data:/mydata:ro instead. References: https://docs.docker.com/storage/bind-mounts/,
https://docs.docker.com/engine/reference/run/#volume-shared-filesystems
NEW QUESTION # 69
Will this action upgrade Docker Engine CE to Docker Engine EE?
Solution.Disable the Docker service via 'chkconfig' or 'systemctl'.
- A. Yes
- B. No
Answer: B
Explanation:
Explanation
The action will not upgrade Docker Engine CE to Docker Engine EE. Disabling the Docker service via chkconfig or systemctl will only stop the Docker daemon from running, but it will not change the version or edition of the Docker engine1. To upgrade Docker Engine CE to Docker Engine EE, you need to follow these steps2:
* Download your Docker Enterprise license from the Docker Store).
* Install the docker-ee package from the Docker repository.
* Restart the Docker service and verify the version and edition. References: Start or stop the Docker daemon), How to upgrade Docker 18.09 Community Edition to Docker Enterprise 18.09)
NEW QUESTION # 70
Will this sequence of steps completely delete an image from disk in the Docker Trusted Registry?
Solution: Delete the image and delete the image repository from Docker Trusted Registry
- A. Yes
- B. No
Answer: B
Explanation:
Explanation
Deleting the image and the image repository from Docker Trusted Registry will not completely delete the image from disk. This is because deleting a repository or a tag only removes the reference to the image, but not the image itself. The image is still stored as a blob on the disk, and can be accessed by its digest1. To completely delete the image from disk, you need to enable the deletion feature in the registry configuration, and then use the API to delete the image by its manifest2. Alternatively, you can manually delete the image files from the registry storage directory, but this is not recommended3. After deleting the image, you also need to run the garbage collector to reclaim the disk space4. References:
* Docker Registry HTTP API V2
* How to delete images from a private docker registry?
* Remove docker image in registry by removing files/folders on server
* Garbage collection
NEW QUESTION # 71
Are these conditions sufficient for Kubernetes to dynamically provision a persistentVolume, assuming there are no limitations on the amount and type of available external storage?
Solution: A default storageClass is specified, and subsequently a persistentVolumeClaim is created.
- A. Yes
- B. No
Answer: A
Explanation:
Explanation
These conditions are sufficient for Kubernetes to dynamically provision a persistentVolume, because a default storageClass provides the information needed to create a persistentVolume that matches the persistentVolumeClaim. According to the official documentation, if no storageClass is specified or requested, then the default one is used.
References: https://kubernetes.io/docs/concepts/storage/dynamic-provisioning/#defaulting-behavior
NEW QUESTION # 72
Will this command ensure that overlay traffic between service tasks is encrypted?
Solution:docker network create -d overlay --secure
- A. Yes
- B. No
Answer: B
Explanation:
= I cannot give you a comprehensive explanation, but I can tell you that the command is not correct. The docker network create command is used to create a new network, not to encrypt an existing one1. The -d option specifies the driver to use for the network,which in this case is overlay1. The overlay driver enables multi-host networking for swarm services2. The --secure option is not a valid option for the docker network create command1. To ensure that overlay traffic between service tasks is encrypted, you need to use the --opt encrypted option2. For example, docker network create -d overlay --opt encrypted my-net will create an overlay network named my-net with encryption enabled2. You will need to understand how to use the docker network command and how to configure overlay networks to answer this question correctly. Reference:
Docker network create command documentation: 1
Overlay network encryption documentation: 2
I hope this helps you prepare for your DCA exam. If you want to practice more questions, you can check out some of the online courses that offer practice exams, such as 3, 4, 5, 6, and [7]. Good luck!
NEW QUESTION # 73
Two pods bear the same label, app: dev.
Will a label selector matching app: dev match both of these pods?
- A. Yes, if the pods are in the same Kubernetes namespace as the object bearing the label selector
- B. Yes, if both pods were pre-existing when the label selector was declared.
- C. Yes, as long as all the containers in those pods are passing their livenessProbes and readinessProbes.
- D. Yes, if the pods are in the same Kubernetes namespace as the object bearing the label selector and both pods were preexisting when the label selector was declared.
Answer: D
NEW QUESTION # 74
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
Answer: B
Explanation:
= The action of using --link to access the container on the bridge network does not accomplish the goal of creating a container that is reachable from its host's network. The --link option allows you to connect containers that are running on the same network, but it does not expose the container's ports to the host1. To create a container that is reachable from its host's network, you need to use the --network host option, which attaches the container to the host's network stack and makes it share the host's IP address2. Alternatively, you can use the --publish or -p option to map the container's ports to the host's ports3.
References: : Legacy container links | Docker Documentation : Networking using the host network | Docker Documentation : docker run reference | Docker Documentation
NEW QUESTION # 75
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 namespace for each application and add all the resources to it.
- A. Yes
- B. No
Answer: A
Explanation:
Explanation
Namespaces in Kubernetes are a way to create and organize virtual clusters within physical clusters where we can isolate a group of resources within a single cluster1. Namespace helps to organize resources such as pods, services, and volumes within the cluster2. By creating one namespace for each application and adding all the resources to it, the development teams can ensure that Kubernetes-specific resources, such as secrets, are grouped together for each application. This also provides a scope for names, a mechanism to attach authorization and policy, and a way to divide cluster resources between multiple users3. References:
* Namespaces | Kubernetes
* Kubernetes - Namespaces - GeeksforGeeks
* Namespaces Walkthrough | Kubernetes
NEW QUESTION # 76
An application image runs in multiple environments, with each environment using different certificates and ports.
Is this a way to provision configuration to containers at runtime?
Solution: Provision a Docker config object for each environment.
- A. Yes
- B. No
Answer: A
NEW QUESTION # 77
Is this a type of Linux kernel namespace that provides container isolation?
Solution: Authentication
- A. Yes
- B. No
Answer: B
Explanation:
Explanation
= Authentication is not a type of Linux kernel namespace that provides container isolation. Namespaces are a feature of the Linux kernel that partitions kernel resources such that one set of processes sees one set of resources and another set of processes sees a different set of resources. Docker uses six different namespaces to isolate containers from the host and from each other: PID, USER, UTS, IPC, MNT, and NET12.
Authentication is not one of them. Authentication is a process of verifying the identity of a user or a system, which is usually done by using credentials such as passwords, tokens, or certificates. Authentication does not directly affect the isolation of containers, although it can be used to control access to them. References:
* Docker security | Docker Docs
* Securing Docker Containers with Linux Kernel Features | Infosec
NEW QUESTION # 78
Which of the following namespaces is disabled by default and must be enabled at Docker engine runtime in order to be used?
- A. user
- B. mnt
- C. pid
- D. net
Answer: A
NEW QUESTION # 79
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Docker DCA certification is a valuable credential for IT professionals working with Docker. It validates an individual’s knowledge and skills in working with Docker and provides a competitive edge in the job market. To prepare for the exam, individuals should have hands-on experience working with Docker and use the resources available, including official documentation, training courses, and practice exams. Passing the Docker DCA exam is a significant achievement and demonstrates a deep understanding of Docker and its capabilities.
Certification Topics of DCA Exam PDF Recently Updated Questions: https://www.actualtestsquiz.com/DCA-test-torrent.html
DCA Certification Sample Questions certification Exam: https://drive.google.com/open?id=14PdcmYkf1HWPNWqxrjQZWs8WIShOwumv
