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Docker Certified Associate Exam Preparation Guide

Docker Certified Associate Exam Preparation Guide (v1.0.1)

This guide is intended to be a point of knowledge for everyone who wants to pass Docker Certified Associate Exam. The main idea is to provide links to every topic in each domain. Preference will always be the official documentation, but feel free to add useful links.

Table of Contents:

1. Orchestration
2. Image Creation, Management, and Registry
3. Installation and Configuration
4. Networking
5. Security
6. Storage and Volumes
7. Links

Content

Domain 1: Orchestration (25% of exam)

• Complete the setup of a swarm mode cluster, with managers and worker nodes
• State the differences between running a container vs running a service
• Demonstrate steps to lock a swarm cluster
• Extend the instructions to run individual containers into running services under swarm
• Interpret the output of "docker inspect" commands
• Convert an application deployment into a stack file using a YAML compose file with "docker stack deploy"
• Manipulate a running stack of services
• Increase number of replicas
• Add networks and published ports: Network on Swarm and network in general with published ports
• Mount volumes
• Illustrate running a replicated vs global service
• Identify the steps needed to troubleshoot a service not deploying
• Apply node labels to demonstrate placement of tasks
• Sketch how a Dockerized application communicates with legacy systems
• Paraphrase the importance of quorum in a swarm cluster
• Demonstrate the usage of templates with "docker service create"

Domain 2: Image Creation, Management, and Registry (20% of exam)

• Describe Dockerfile options (add, copy, volumes, expose, entrypoint, etc)
• Show the main parts of a Dockerfile
• Give examples on how to create an efficient image via a Dockerfile
• Use CLI commands such as list, delete, prune, rmi, etc to manage images
• Inspect images and report specific attributes using filter and format
• Demonstrate tagging an image
• Utilize a registry to store an image
• Display layers of a Docker image
• Apply a file to create a Docker image
• Modify an image to a single layer
• Describe how image layers work
• Deploy a registry (not architect)
• Configure a registry
• Log into a registry
• Utilize search in a registry
• Tag an image
• Push an image to a registry
• Sign an image in a registry
• Pull an image from a registry
• Describe how image deletion works. Pruning and removing
• Delete an image from a registry

Domain 3: Installation and Configuration (15% of exam)

• Demonstrate the ability to upgrade the Docker engine
• Complete setup of repo, select a storage driver, and complete installation of Docker engine on multiple platforms
• Configure logging drivers (splunk, journald, etc)
• Setup swarm, configure managers, add nodes, and setup backup schedule
• Create and manage user and teams
• Interpret errors to troubleshoot installation issues without assistance
• Outline the sizing requirements prior to installation
• Understand namespaces, cgroups, and configuration of certificates
• Use certificate-based client-server authentication to ensure a Docker daemon has the rights to access images on a registry
• Consistently repeat steps to deploy Docker engine, UCP, and DTR on AWS and on premises in an HA config. Docker, DTR, UCP,, Docker on AWS and possibly on premises HA config
• Complete configuration of backups for UCP and DTR
• Configure the Docker daemon to start on boot

Domain 4: Networking (15% of exam)

• Create a Docker bridge network for a developer to use for their containers
• Troubleshoot container and engine logs to understand a connectivity issue between containers
• Publish a port so that an application is accessible externally
• Identify which IP and port a container is externally accessible on
• Describe the different types and use cases for the built-in network drivers
• Understand the Container Network Model and how it interfaces with the Docker engine and network and IPAM drivers
• Configure Docker to use external DNS
• Use Docker to load balance HTTP/HTTPs traffic to an application (Configure L7 load balancing with Docker EE)
• Understand and describe the types of traffic that flow between the Docker engine, registry, and UCP controllers
• Deploy a service on a Docker overlay network
• Describe the difference between "host" and "ingress" port publishing mode (Host, Ingress)

Domain 5: Security (15% of exam)

• Describe the process of signing an image
• Demonstrate that an image passes a security scan
• Enable Docker Content Trust
• Configure RBAC in UCP
• Integrate UCP with LDAP/AD
• Demonstrate creation of UCP client bundles
• Describe default engine security
• Describe swarm default security
• Describe MTLS
• Identity roles
• Describe the difference between UCP workers and managers
• Describe process to use external certificates with UCP and DTR (UCP from cli, from GUI, print the public certificates), DTR)

Domain 6: Storage and Volumes (10% of exam)

• State which graph driver should be used on which OS
• Demonstrate how to configure devicemapper
• Compare object storage to block storage, and explain which one is preferable when available
• Summarize how an application is composed of layers and where those layers reside on the filesystem
• Describe how volumes are used with Docker for persistent storage
• Identify the steps you would take to clean up unused images on a filesystem, also on DTR. (image prune, system prune and from DTR)
• Demonstrate how storage can be used across cluster nodes

Quick facts about the exam

Summary

These are the most relevant quick facts of the exam:

• The exam is online, using Google Chrome browser on Windows or MacOS ONLY. Linux support IS NOT available at this time;
• 55 questions to be answered within 90 minutes. Which give you almost one minute and a half to spend on each question;
• It costs 195 USD or 175 EUR;
• Lasts for 2 years after the day you got certified;
• Docker does not publish exam passing scores because exam questions and passing scores are subject to change without notice;
• Results comes instantly.

More detailed parts about the exam, please refer to the Links section.

Question format

All the questions follow this strucuture: ONE question and FOUR different possible answers.

With that in mind, there are TWO TYPES of giving answers:

• ONE RIGHT ANSWER: The answer options will be a clickable spot and you must select ONE CHOICE. This can be either select a valid answer in a true/false statement or a fill in blank example.
• MULTIPLE ANSWERS: The answer option will be a square-type and accepts MULTIPLE CHOICES. Before checking the answers, please refer to the question to ensure HOW MANY VALID CHOICES ARE.

There are no boolean questions (statement and then choose between True or False).

Links

• About the exam
• Official study guide (PDF)

Contributors

Thanks to all contributors!

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