docker2

Which of the following is NOT how to create an efficient image via a Dockerfile?. Avoid installing unnecessary packages. Start with an appropriate base image. Combine multiple applications into a single container. Use multi-stage builds.

What is the docker command for displaying layers of a Docker image?. docker image layers. docker layers. docker info. docker history.

What is used by the kernel to isolate resources when running Docker containers?. Volumes. Overlay networks. Control groups. Namespaces.

What Dockerfile option LABEL does?. Tells Docker how to test a container to check that it is still working. Label a container that will run as an executable. Adds metadata to an image. Provide defaults for an executing container.

What is the difference between the ADD and COPY dockerfile instructions? (choosen 2). ADD supports compression format handling while COPY does not. COPY supports regular expression handling while ADD does not. COPY supports compression format handling while ADD does not. ADD supports regular expression handling while COPY does not. ADD support remote URL handling while COPY does not.

Which of the following is the correct command to store an image to a registry?. docker upload [OPTIONS] NAME[:TAG]. docker store [OPTIONS] NAME[:TAG]. docker push [OPTIONS] NAME[:TAG]. docker commit [OPTIONS] NAME[:TAG].

Which of the following statements is incorrect?. When a container is deleted, the writable layer is persisted. The column 'virtual size' of docker ps -s output shows the amount of data used for the read-only image data used by the container plus the container's writable layer 'size'. Copy-on-write is a Docker strategy of sharing and copying files for maximum efficiency. The column 'size' of docker ps -s output shows the amount of data that is used for the writable layer of each container.

Which option the Dockerfile will appear in the end ? FROM alpine:latest WORKDIR /a WORKDIR b WORKDIR c CMD [ '/bin/bash', 'pwd' ]. /a. /a/b/c. c. b.

Which constraint role you use if you want to restrict a service to be scheduled in a manager in the Swarm cluster?. swarm.role != worker. node.role == manager. swarm.role == manager. node.role != manager.

Which of the Dockerfile options executes any commands in a new layer on top of the current image and commit the results?. RUN. FROM. ONBUILD. CMD.

Which of the following is NOT a valid way to tag a Docker image?. Tag an image referenced by user ID. Tag an image referenced by Name. Tag an image referenced by image ID. Tag an image referenced by Name and Tag.

When seven managers are in a swarm cluster, how would they be distributed across three datacenters or availability zones?. 36983. 37317. 36953. 37012.

What Dockerfile instructions create new layers on the top of a image?. RUN (Correct). COPY (Correct). ADD (Correct). CMD.

How can you list exited containers ? ( Select all that apply ). docker container list exited. docker ps -f 'Exited'. docker container ls -f 'status=exited' (Correct). docker ps -a - grep Exited (Correct).

When you deploy UCP, it starts running a globally scheduled service called ucp-agent, this service monitors the node where it’s running and starts and stops UCP services, based on whether the node is a manager or a worker node. If the node is a manager node, how does ucp-agent will work on this node ?. The ucp-agent service starts serving a proxy service that ensures only authorized users and other UCP services can run Docker commands in that node. The ucp-agent deploys a subset of containers on these nodes. The ucp-agent service automatically starts serving all UCP components, including the UCP web UI and data stores used by UCP. The ucp-agent accomplishes this by deploying several containers on the node.

You can monitor the status of UCP by using the web UI or the CLI. You can also use the _ping endpoint to build monitoring automation. yes. no.

Pod Security Policies (PSPs) are cluster-level resources that are enabled by default in UCP 3.2.UCP uses its own role-based access control (RBAC) for Kubernetes clusters. Which of the following role-grants does Kubernetes provide?. NodeRoleBinding. PodRoleBinding. UserRoleBinding. ClusterRoleBinding. RoleBinding.

By default, when you push an image to DTR, the Docker CLI client doesn’t sign the image.You can configure the Docker CLI client to sign the images you push to DTR. That way, what are the steps needed to sign an image ?. Initialize trust metadata for the repository. Configure your Notary client. Push private keys to DTR server. Delegate signing to the keys in your UCP client bundle.

In a DevOps environment, 10 nodes are working as part of the swarm cluster. According to business rules, there is a requirement to only allow containers based on Kubernetes orchestrator .Which of the following commands below it will enable Docker achieving this rule?. docker node update --label-add com.ucp.orchestrator.kubernetes=true. docker node update --label-add com.docker.ucp.orchestrator.kubernetes=true. docker node --label--add com.docker.ucp.orchestrator.kubernetes=true. docker node add --label-add com.orchestrator.kubernetes=true.

By default, how many layers of docker image does docker daemon pull from the docker registry at a time?. 2. 4. 1. 3.

A ____ is a running container which is part of a swarm service and managed by a swarm manager, as opposed to a standalone container. instance. image. task. node.

What is the docker command to add or update a mount on a service?. docker service update --mount-add type=volume,source=other-volume,target=/somewhere-else myservice. docker service --add-update-mount type=volume,source=other-volume,target=/somewhere-else myservice. docker service --mount-volume type=volume,source=other-volume,target=/somewhere-else myservice. docker service set --add-update-mount type=volume,source=other-volume,target=/somewhere-else myservice.

Which network allows Docker Trusted Registry components running on different nodes to communicate which each other and replicate Docker Trusted Registry data?. dtr-br. dtr-ol. dtr-hosts. dtr-vlan.

Which of the following is a step in backing up the Docker Swarm?. Back up the contents of /var/lib/docker/swarm on a Swarm manager. Back up the layered file systems of all containers running within the swarm. Back up the contents of /etc/docker on a Swarm manager. Back up the contents of /etc/docker/swarm on a Swarm manager.

Which of the following is not an endpoint exposed by Docker Trusted Registry (DTR) that can be used to assess the health of a Docker Trusted Registry replica?. /nginx_status. /replica_status. /api/v0/meta/cluster_status. /health.

To decrease the time to pull images for geographically dispersed users you can configure which DTR option?. DTR CDN. DTR Local Registry. DTR Edge. DTR cache.

Which command can you use on a node to join the current node to the swarm cluster as a worker node?. None of the above. docker swarm join --token. docker swarm join worker. docker swarm --join --token.

To configure Docker daemon to start as the system boots up, which of the following commands is correct for most Linux distributions?. sudo systemctl start docker. sudo systemctl default docker. sudo systemctl enable docker. sudo systemctl up docker.

Which of the following options best describes the procedure for backing up the Universal Control Plane (UCP) metadata?. Create an archive for all of the data under the /etc/docker/ucp directory. Run a container from the ucp image with the uninstall-ucp command. Create an archive for all of the data under the /var/data/ucp directory. Run a container from the ucp image with the backup command.

Which modes does Docker provide for delivering messages from the container to the log driver?. blocking. syncrhonous. asynchronous. non-blocking.

Which is the recommended way to installed Docker Engine on a production server?. Install using the convenience script. None of the above. Install from a package. Install using the repository.

How can you configure the Docker daemon to start as the system boots up? (select two). Use systemd for most current Linux distributions (RHEL, CentOS, Fedora, Ubuntu 16.04 and higher). Use upstart for Ubuntu 14.10 and below. Use crond for Ubuntu 14.10 and below. Use startup for most current Linux distributions (RHEL, CentOS, Fedora, Ubuntu 16.04 and higher).

Which of the following technologies make up container format? (select three). Docker control plane. UnionFS. Control Groups. Namespaces. Docker Daemon.

What are the hardware and software requirements to install Docker Trusted Registry (DTR)? (select all that apply). All nodes must be a worker node managed by Universal Control Plan. Make sure the port 8080 and 8443 are open on the node. DTR can be installed on-premises or on a cloud provider. All nodes must have fixed hostname.

You are using self-signed UCP certs and have a second DNS name that points to your internal controllers (UCP). When installing UCP, which flag should you use to add this additional name?. -external-server-cert. --san. --dns. --internal-server-cert.

Which of the following commands will set the Docker engine into debug mode?. echo '{"debug": true}' > /etc/docker/config.json ; sudo kill -HUP. echo '{"debug": true}' > /var/lib/docker/config.json ; sudo kill -HUP. echo '{"debug": true}' > /etc/docker/daemon.json ; sudo kill -HUP. echo '{"debug": true}' > /var/lib/docker/daemon.json ; sudo kill -HUP.

Which storage driver is used by default when installing Docker?. ext4. brtfs. overlay2. zfs.

Which type of mount is best when you need to back up, restore, or migrate data from one Docker host to another?. tempfs. bind mounts. volumes. Regular.