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Question 1

(0)

Will this command display a list of volumes for a specific container? Solution. 'docker container inspect nginx'

Question 2

(0)

Is this an advantage of multi-stage builds? Solution. better logical separation of Dockerfile instructions for increased readability

Question 3

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Does this command create a swarm service that only listens on port 53 using the UDP protocol? Solution. 'docker service create -name dns-cache -p 53:53 -constraint networking.protocol.udp=true dns-

Question 4

(0)

Does this command create a swarm service that only listens on port 53 using the UDP protocol? Solution. 'docker service create -name dns-cache -p 53:53/udp dns-cache'

Question 5

(0)

During development of an application meant to be orchestrated by Kubernetes, you want to mount the /data directory on your laptop into a container. Will this strategy successfully accomplish this?

Question 6

(0)

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?

Question 7

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Is this an advantage of multi-stage builds? Solution: better caching when building Docker images

Question 8

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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 persi

Question 9

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You add a new user to the engineering organization in DTR. Will this action grant them read/write access to the engineering/api repository? Solution. Mirror the engineering/api repository to one o

Question 10

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Is this the purpose of Docker Content Trust? Solution. Sign and verify image tags.

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Related questions

The Kubernetes yaml shown below describes a networkPolicy. Will the networkPolicy BLOCK this traffic? Solution: a request issued from a pod lacking the tier: api label, to a pod bearing the tier: backend label

Does this command create a swarm service that only listens on port 53 using the UDP protocol? Solution. 'docker service create -name dns-cache -p 53:53 -constraint networking.protocol.udp=true dns-cache'

Is this a supported user authentication method for Universal Control Plane? Solution. x.500

Will this command display a list of volumes for a specific container? Solution. 'docker container logs nginx --volumes'

Is this a way to configure the Docker engine to use a registry without a trusted TLS certificate? Solution. Set INSECURE_REGISTRY in the' /etc/docker/default' configuration file.

The Kubernetes yaml shown below describes a clusterIP service. Is this a correct statement about how this service routes requests? Solution: Traffic sent to the IP of this service on port 8080 will be routed to port 80 in a random pod with the label aPP: nginx.

A Kubernetes node is allocated a /26 CIDR block (64 unique IPs) for its address space. If every pod on this node has exactly two containers in it, how many pods can this address space support on this node?

Will this command list all nodes in a swarm cluster from the command line? Solution. 'docker inspect nodes

A user's attempts to set the system time from inside a Docker container are unsuccessful. Could this be blocking this operation? Solution. SELinux

Will this command display a list of volumes for a specific container? Solution: docker volume inspect nginx'

Question 153 - DCA discussion

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Seven managers are in a swarm cluster.

Is this how should they be distributed across three datacenters or availability zones?

Solution: 4-2-1

A.

Yes

B.

No

Suggested answer: B

Explanation:

This is not how the seven managers should be distributed across three datacenters or availability zones.A swarm cluster is a group of Docker hosts that are running in swarm mode and act as managers or workers1.A manager node is responsible for maintaining the swarm state and orchestrating the services2.A swarm cluster needs a quorum of managers to operate, which means a majority of managers must be available and able to communicate with each other3.

The problem with distributing the seven managers as 4-2-1 is that it creates a split-brain scenario, where the cluster can lose the quorum if one datacenter or availability zone fails. For example, if the datacenter with four managers goes down, the remaining three managers will not have enough votes to form a quorum, and the cluster will stop functioning.Similarly, if the datacenter with one manager goes down, the cluster will lose the tie-breaking vote and will not be able to elect a leader4.

A better way to distribute the seven managers across three datacenters or availability zones is to use 3-2-2, which ensures that the cluster can tolerate the failure of any one datacenter or availability zone and still maintain the quorum. For example, if the datacenter with three managers goes down, the remaining four managers will have enough votes to form a quorum and elect a leader.Similarly, if the datacenter with two managers goes down, the remaining five managers will have enough votes to form a quorum and elect a leader4.Reference:

Swarm mode overview | Docker Docs

Administer and maintain a swarm of Docker Engines | Docker Docs

Raft consensus in swarm mode | Docker Docs

Docker Swarm: How to distribute managers across availability zones? - Stack Overflow

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asked 08/11/2024

Mohammed Hamid

46 questions

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Your answer: A B

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