Mixed Deck — All DCA Topics Flashcards

Which log driver is the default for Docker containers when no driver is explicitly configured?

Answer: json-file

By default, Docker uses the `json-file` log driver, storing logs as JSON on the host filesystem.

You want `docker logs` to follow output in real time, similar to `tail -f`. Which flag do you use?

Answer: --follow

`docker logs --follow` (or `-f`) continuously streams new log output as the container produces it.

A project architect must ensure containers in different Docker networks cannot communicate unless explicitly allowed. What feature enforces this?

Answer: By default, containers on different networks are isolated from each other

Docker network isolation is the default; containers on separate networks cannot communicate unless connected to a shared network.

What is the purpose of financial forecasting in DCA practice?

Answer: To predict future financial conditions based on historical data and current trends

Financial forecasting uses historical data, current trends, and assumptions to project future revenues, expenses, and financial position, supporting strategic planning and resource allocation decisions.

A team is planning Docker image layer caching strategy in their CI system. Which Dockerfile instruction order maximizes cache reuse?

Answer: RUN dependency installation first using lockfiles, then COPY application source

Copying only the lockfile and installing dependencies before copying source code allows the dependency layer to be cached across code changes.

A project plan calls for image scanning before deployment. Which Docker CLI command initiates a vulnerability scan using Docker Scout?

Answer: docker scout cves

The 'docker scout cves' command lists known CVEs in an image using the Docker Scout service.

Which command lists all nodes currently participating in a Docker Swarm?

Answer: docker node ls

`docker node ls` lists every node in the Swarm along with its role, status, and availability.

You want to capture a single snapshot of container stats without streaming continuously. Which flag achieves this?

Answer: --no-stream

`docker stats --no-stream` outputs one set of stats and exits instead of continuously streaming.

What is the primary purpose of a code of ethics in DCA practice?

Answer: To establish professional standards of conduct and guide ethical decision-making

A code of ethics provides a framework of professional values and behavioral standards that guides practitioners in ethical decisions while maintaining public trust.

What is multi-factor authentication (MFA) in DCA security?

Answer: A security method requiring two or more verification factors to gain access

MFA requires users to provide two or more distinct verification factors (something they know, something they have, something they are) before gaining access, significantly reducing unauthorized access risk.

What is the difference between quality assurance and quality control in DCA practice?

Answer: QA focuses on preventing defects through processes; QC focuses on detecting defects in outputs

Quality assurance is proactive and process-oriented, designed to prevent defects. Quality control is reactive and product-oriented, focused on identifying defects in finished outputs through inspection and testing.

What is the purpose of data analysis in DCA practice?

Answer: To transform raw data into meaningful insights that support informed decision-making

Data analysis involves examining, cleaning, transforming, and modeling data to discover useful information, draw conclusions, and support decision-making processes with evidence-based insights.

How are Docker secrets passed to a container in Swarm mode?

Answer: As files mounted under /run/secrets/ inside the container

Docker secrets are mounted as in-memory tmpfs files at /run/secrets/ inside the container, never exposed in environment variables or image layers.

What is the purpose of a risk matrix in DCA practice?

Answer: To evaluate risks by plotting likelihood against severity of potential impact

A risk matrix plots the probability of occurrence against the severity of potential consequences, helping prioritize which risks need immediate attention and which can be monitored.

A security scan finds a critical CVE in a base image. What is the recommended remediation workflow in a Docker-based CI/CD pipeline?

Answer: Update the base image tag in the Dockerfile, rebuild, re-scan, and redeploy

The correct remediation is to update the Dockerfile to a patched base image version, rebuild from source, verify with a new scan, and redeploy to eliminate the vulnerability.

What format is used to define a custom seccomp profile for a Docker container?

Answer: A JSON profile file

Docker seccomp profiles are defined in JSON format, specifying the default action and the list of allowed or denied system calls.

In Docker Swarm, what is a 'task'?

Answer: A running container instance that is part of a service

A task is the atomic scheduling unit in Swarm — it represents a single running container that belongs to a service.

Which of the subsequent patterns would prevent any Python byte-code files from being copied during the building of a Docker image?

Answer: **/*.pyc

Docker provides a special wildcard string ** that matches any number of folders in addition to Go's filepath. Match rules (including zero). For instance, **/*.go will exclude all files with the.go extension that are present in any directory, including the build context's root.

What is the purpose of signing Docker images with 'docker trust sign'?

Answer: It creates a cryptographic signature so consumers can verify the image has not been tampered with

Docker Content Trust (DCT) uses Notary to create digital signatures, allowing clients to verify image integrity and publisher identity before pulling.

Why is data visualization important in DCA reporting?

Answer: It makes complex data patterns and relationships easier to understand and communicate

Data visualization translates complex datasets into visual formats (charts, graphs, maps) that highlight patterns, trends, and outliers, making information more accessible and actionable for diverse audiences.