DCA Docker Swarm & Orchestration 2

Question 1

What is the minimum number of manager nodes required so that a Docker Swarm can tolerate the failure of one manager?

Accepted Answer

3

Answer

1

Answer

2

Answer

4

Question 2

What does the Raft consensus algorithm provide in a Docker Swarm cluster?

Accepted Answer

Consistent distributed state management across manager nodes

Answer

Load balancing of tasks across worker nodes

Answer

Container-to-container networking between nodes

Answer

Automatic service discovery for containers

Question 3

Which command sets the availability of a Swarm node named 'node1' to 'drain'?

Accepted Answer

docker node update --availability drain node1

Answer

docker swarm drain node1

Answer

docker node drain node1

Answer

docker node set --drain node1

Question 4

What is a Docker Stack in the context of Swarm mode?

Accepted Answer

A group of interrelated services deployed together using a Compose-format file

Answer

A collection of Docker images stored in a private registry

Answer

A set of Swarm manager nodes forming a control plane

Answer

A storage driver for managing persistent volumes

Question 5

Which command deploys a stack named 'myapp' to a Swarm using 'docker-compose.yml'?

Accepted Answer

docker stack deploy -c docker-compose.yml myapp

Answer

docker compose up --swarm myapp

Answer

docker swarm deploy --file docker-compose.yml myapp

Answer

docker stack create --compose docker-compose.yml myapp

Question 6

What happens to a node's ability to run service tasks after it is promoted from worker to manager in Docker Swarm?

Accepted Answer

The node continues running tasks while also performing management functions

Answer

All existing tasks on the node are immediately stopped

Answer

The node stops running tasks and only handles management duties

Answer

Tasks are migrated automatically to remaining worker nodes

Question 7

What is a service 'placement constraint' in Docker Swarm?

Accepted Answer

A rule that restricts which nodes are eligible to run a service's tasks

Answer

A CPU/memory resource limit applied to service containers

Answer

A maximum replica count enforced by the scheduler

Answer

A health check condition required before a task is marked healthy