Which of the following will upload a new stack to your Docker Cloud account?
- docker-cloud stack create docker-cloud.yml
- docker-cloud stack create -f docker-cloud.yml (Ans)
- docker-cloud stack create -f dockerfile
- docker stack create -f docker-cloud.yml
Docker Engine is:
- The locally installed runtime through which you administrate Docker containers (Ans)
- An online Docker administration interface
- An online Docker image repository
- A local Docker image repository
Docker Trusted Registry is:
- A local, commercial image management tool
- An open source tool for securing the infrastructure on which Docker Engine runs
- A web-based, commercial, hosted image management tool (Ans)
- An open source tool for coordinating Docker container clusters
A Docker container will run faster when its image is properly optimized. Which of the following will have the greatest positive impact on speed?
- Build the image using as few layers as possible. (Ans)
- Always base your images on the latest operating system version available.
- Always be consistent in the software package versions you choose for your image layers.
- Build the image using a Dockerfile rather than from a running container.
Where are the image files stored on a Linux machine running a package-based Docker Registry?
- /var/lib/docker/docker-registry/docker/registry/v2/repositories (Ans)
Which of these commands will return a list of images currently stored in a Docker Registry?
- docker images
- curl 192.168.1.17:5000/v2/_catalog (Ans)
- curl 192.168.1.17:5000/v2/_data
- docker registry ls
Which of the following commands will successfully build an image with the name “myimage”?
- docker build -t myimage
- docker build –tag-image myimage
- docker build -n myimage .
- docker build -t myimage . (Ans)
What does “retries” specify for a health check?
- How many times a container is restarted before it’s marked unhealthy
- How many times an individual health check is simultaneously performed before assuming a failure
- How many times a container is restarted before its task is shutdown and a new one is created
- How many times a health check fails before a container is marked unhealthy (Ans)
docker-compose is roughly equivalent to what swarm mode command: __?
- docker stack deploy (Ans)
- docker service create
- docker run
What purpose does the ingress network serve?
- Routing traffic from published ports to running containers (Ans)
- Load balancing internal container to container traffic
- Routing internal container to container traffic
How are secrets made available to a container?
- Environment Variables
- Filesystem (Ans)
- HTTP API
Pinning is the process of ______?
- Resolving an image tag to a digest (Ans)
- Assigning a image repository to a digest
- Assigning a task to a node
- Assigning a container to a task
- Resolving a image digest to a tag
Which published port mode would you use to map the port on a given node to a specific container running on that node?
- Host (Ans)
Services are a template for:
- Tasks (Ans)
If you only have a global service, what will happen when you add a new node to the cluster?
- The pending task for the service will be assigned to the new node and a container will be started.
- A new task will be allocated to the new node for the global service. (Ans)
- The existing containers for the service will be rebalanced so that a fair share are placed onto the new node.
- Nothing will run on the new node unless you change the service.
Let’s say you have a service with four replicas, and four tasks currently running with IDs: A, B, C, and D. Let’s say you stop the container associated with task D.
- The service is terminated.
- A new task E and a new container are created. Task D and its container are removed. (Ans)
- The container is restarted.
- The container is removed, and a new one is created and associated with Task D.
What happens if you try to view cluster state from a worker only node?
- List of cluster state for all nodes
- List of state for that worker node only
- An error (Ans)
How can you see a log of health checks?
- docker service ps MYSERVICE
- docker ps
- docker inspect CID (Ans)
- docker service inspect MYSERVICE
- docker stack ps MYSTACK
If you want to convert a worker node into a manager node, what do you use?
- docker node demote
- docker swarm worker
- docker swarm manager
- docker node promote (Ans)
- docker node rm
A stack manages multiple:
- Services (Ans)
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