DCA Exam Dumps : Docker Certified Associate (DCA) Exam

 In the context of a swarm mode cluster, an instance of the Docker engine participating in the swarm is indeed a node1. A node can be either a manager or a worker, depending on the role assigned by the swarm manager2. A manager node handles the orchestration and management of the swarm, while a worker node executes the tasks assigned by the manager2. A node can join or leave a swarm at any time, and the swarm manager will reconcile the desired state of the cluster accordingly1. References:

1: Swarm mode overview | Docker Docs

2: Manage nodes in a swarm | Docker Docs

The statement is incorrect about the health check definition based on the Docker Compose file provided. According to the Docker documentation, a health check can be specified in a Dockerfile or a Docker Compose file to tell Docker how to test a container to check that it is still working. This can be done with options such asinterval,timeout, andretries. In this case, the health checks are not set to test five seconds apart but rather ten seconds apart (interval: 10s).Theretries: 3indicates that if the health check fails, Docker will try three times before considering the container unhealthy1.

The set of commands docker container inspect and docker port cannot identify the published port(s) for a container. The docker container inspect command returns low-level information on a container, such as its ID, name, state, network settings, mounts, etc1. However, it does not show the port mappings between the container and the host2. The docker port command lists the port mappings or a specific mapping for a container, but it requires the container name or ID as an argument3. Therefore, to identify the published port(s) for a container, you need to use both commands together, such as docker port $(docker container inspect -f '{{.Name}}' CONTAINER)4. References:

docker container inspect | Docker Docs

How to inspect a running Docker container - Stack Overflow

docker port | Docker Docs

List port for Docker container using command line - Stack Overflow