Download Cloud Foundry Certified Developer Beta Certification Exam Preparation Guide [CFCDB] and more Exams Technology in PDF only on Docsity!
Exam Preparation Guide [CFCDB]
Question 1. Which component is primarily responsible for scheduling application containers onto Diego cells? A) Cloud Controller B) Router C) Diego Brain D) Loggregator Answer: C Explanation: The Diego Brain (part of the Diego system) makes placement decisions and schedules containers onto Diego cells. Question 2. In the cf CLI hierarchy, what is the immediate parent of a Space? A) Organization B) Application C) Service Instance D) Route Answer: A Explanation: A Space belongs to an Organization; Organizations contain multiple Spaces. Question 3. Which cf CLI command authenticates a user to a Cloud Foundry API endpoint? A) cf login B) cf target C) cf auth D) cf push Answer: A Explanation: cf login prompts for credentials and authenticates the user against the targeted API endpoint. Question 4. Which role can create and delete Organizations? A) OrgManager B) OrgAuditor C) SpaceDeveloper
Exam Preparation Guide [CFCDB]
D) SpaceManager Answer: A Explanation: OrgManager has full control over an Organization, including creating and deleting it. Question 5. When executing cf push, what stage occurs immediately after the application bits are uploaded? A) Running B) Staging C) Routing D) Scaling Answer: B Explanation: After upload, Cloud Foundry stages the app (buildpack execution) before it can be run. Question 6. Which buildpack detection file indicates that a Java application uses Maven? A) pom.xml B) build.gradle C) package.json D) requirements.txt Answer: A Explanation: Presence of pom.xml triggers the Java buildpack to detect a Maven project. Question 7. Which health check type verifies that an application is listening on its assigned port? A) process B) port C) http D) tcp Answer: B Explanation: The “port” health check ensures the app is bound to the port assigned by Cloud Foundry.
Exam Preparation Guide [CFCDB]
D) cf service‑bindings Answer: B Explanation: cf marketplace displays all service offerings that can be provisioned. Question 12. When creating a managed service instance, which flag specifies the plan to use? A) – service-plan B) – plan C) – type D) – instance‑type Answer: B Explanation: --plan selects the desired service plan during cf create-service. Question 13. After binding a service to an app, how are the credentials made available to the app at runtime? A) As command‑line arguments B) In a mounted volume C) Injected into VCAP_SERVICES environment variable D) Written to a config file in /tmp Answer: C Explanation: Cloud Foundry injects service credentials into the VCAP_SERVICES env var. Question 14. Which type of service instance is used to bind an app to an external database not listed in the marketplace? A) Managed Service Instance B) User‑Provided Service Instance (UPSI) C) Service Key D) Shared Service Instance Answer: B Explanation: UPSIs allow developers to define arbitrary credentials for external resources. Question 15. What is the purpose of a service key in Cloud Foundry?
Exam Preparation Guide [CFCDB]
A) To bind an app to a service B) To provide out‑of‑band credentials for external tools C) To delete a service instance D) To share a service across spaces Answer: B Explanation: Service keys generate credentials that external applications or CI pipelines can use. Question 16. Which command shares a service instance from one space to another within the same organization? A) cf share-service SERVICE – space TARGET_SPACE B) cf bind-service TARGET_SPACE SERVICE C) cf copy-service SERVICE TARGET_SPACE D) cf service‑share SERVICE TARGET_SPACE Answer: A Explanation: cf share-service enables service instance sharing across spaces. Question 17. What is the default domain type used when you issue cf push without specifying a domain? A) Private domain B) Shared domain C) Custom domain D) TCP domain Answer: B Explanation: Cloud Foundry automatically uses a shared domain (provided by the platform) if none is specified. Question 18. Which cf CLI command creates a new route without binding it to any app? A) cf create-route my-org my-space example.com – hostname app B) cf map-route my-app example.com – hostname app C) cf push – no-route D) cf unmap-route my-app example.com – hostname app
Exam Preparation Guide [CFCDB]
A) – tail B) – recent C) – all D) – since‑start Answer: B Explanation: cf logs APP --recent fetches the recent log buffer from the Loggregator system. Question 23. Which cf CLI command displays a chronological list of events for an application? A) cf logs APP B) cf events APP C) cf app‑events APP D) cf history APP Answer: B Explanation: cf events APP lists app lifecycle events such as START, STOP, CRASH. Question 24. What must be enabled to allow cf ssh into an application container? A) SSH is always enabled by default B) Set the ssh_enabled property on the org C) cf enable-ssh APP D) Add the user to the SpaceDeveloper role Answer: C Explanation: cf enable-ssh APP turns on SSH access for that specific app. Question 25. A staging error that mentions “No matching buildpack found” most likely indicates what? A) The app exceeded its memory quota B) The required runtime is not supported by any installed buildpack C) The route is misconfigured D) The user lacks OrgManager permissions Answer: B
Exam Preparation Guide [CFCDB]
Explanation: Buildpack detection failed because none of the available buildpacks recognize the app’s source. Question 26. Which quota limit would cause an app push to fail with “Insufficient memory”? A) Instance count quota B) Disk quota per app C) Organization memory quota D) Service instance quota Answer: C Explanation: Organization memory quota caps total memory usage across all apps; exceeding it aborts the push. Question 27. According to the 12‑Factor App methodology, which factor emphasizes storing config in the environment? A) Codebase B) Dependencies C) Config D) Port binding Answer: C Explanation: Factor III states that config should be stored in environment variables, not in the code. Question 28. Which 12‑Factor principle recommends that an app should expose services via binding to a port rather than hard‑coding URLs? A) Port binding B) Concurrency C) Statelessness D) Build, release, run Answer: A Explanation: Factor VII (“Port binding”) dictates that the app should be self‑contained and listen on a port. Question 29. In a microservices architecture on Cloud Foundry, what mechanism is typically used for service discovery?
Exam Preparation Guide [CFCDB]
D) cf env Answer: B Explanation: cf target reports the API endpoint, org, and space currently targeted. Question 33. What does the “diego” component replace from the original Cloud Foundry architecture? A) DEA (Droplet Execution Agent) B) Router C) Loggregator D) UAA Answer: A Explanation: Diego supersedes the older DEA for container scheduling and execution. Question 34. Which of the following is NOT a default user role in Cloud Foundry? A) OrgAuditor B) SpaceDeveloper C) SpaceManager D) ServiceAdmin Answer: D Explanation: There is no built‑in “ServiceAdmin” role; service permissions are managed via service brokers. Question 35. When scaling an app horizontally to three instances, which command is used? A) cf scale APP - i 3 B) cf scale APP - m 3G C) cf set-instances APP 3 D) cf resize APP – instances 3 Answer: A Explanation: -i flag sets the instance count; cf scale APP - i 3 creates three instances. Question 36. Which log streaming command continuously streams live logs until interrupted?
Exam Preparation Guide [CFCDB]
A) cf logs APP – tail B) cf logs APP – recent C) cf tail APP D) cf stream APP Answer: A Explanation: --tail keeps the connection open, streaming logs in real time. Question 37. If an application’s health check fails repeatedly, what is the most likely immediate outcome? A) The app is automatically restarted B) The app’s route is removed C) The app’s memory quota is increased D) The app’s instances are scaled down to zero Answer: A Explanation: Failed health checks cause the Diego cell to restart the affected container. Question 38. Which command lists all routes that are currently mapped to an app? A) cf routes APP B) cf app APP – guid C) cf map-route – list APP D) cf routes – app APP Answer: A Explanation: cf routes APP shows the routes associated with the specified app. Question 39. What does the “shared domain” feature allow tenants to do? A) Use a common domain name for all apps without needing a private domain B) Create isolated DNS zones per organization C) Host TCP services only D) Bypass the router completely Answer: A
Exam Preparation Guide [CFCDB]
B) Credentials are stored centrally and accessed via a shared volume C) The same VCAP_SERVICES entry is injected into each app’s environment D) Only the first bound app receives credentials Answer: C Explanation: Binding injects the same credentials into each app’s VCAP_SERVICES environment variable. Question 44. Which command deletes a user‑provided service instance? A) cf delete-service UPSI_NAME B) cf purge-service UPSI_NAME C) cf remove-upsi UPSI_NAME D) cf unbind-service UPSI_NAME Answer: A Explanation: cf delete-service removes both managed and user‑provided service instances. Question 45. What does the “port” health check type NOT verify? A) That the process is running B) That the app is listening on the assigned port C) That the app returns a 200 OK on HTTP D) That the container’s network stack is functional Answer: C Explanation: “port” health check only checks socket listening, not HTTP response codes. Question 46. Which Cloud Foundry component aggregates metrics and events for monitoring? A) Loggregator B) Diego Brain C) Cloud Controller D) Router Answer: A Explanation: Loggregator collects logs, metrics, and events from the platform.
Exam Preparation Guide [CFCDB]
Question 47. To override the default health check for an app to “process”, which command is used? A) cf set-health-check APP process B) cf set-health-check APP port C) cf set-health-check APP http D) cf change-health-check APP process Answer: A Explanation: cf set-health-check changes the health check type for the specified app. Question 48. Which command shows the current memory and disk usage of an app instance? A) cf app APP – guid B) cf stats APP C) cf instance‑stats APP D) cf usage APP Answer: B Explanation: cf stats displays per‑instance memory, disk, and CPU usage. Question 49. When using a custom buildpack, which file must be present at the root of the buildpack repository? A) buildpack.toml B) manifest.yml C) bin/detect D) config.json Answer: C Explanation: The bin/detect script determines whether the buildpack applies to the app. Question 50. Which flag is required to push an app using a specific buildpack that is not auto‑detected? A) – buildpack BUILDPACK_URL B) – custom-buildpack BUILDPACK_URL C) – use-buildpack BUILDPACK_URL
Exam Preparation Guide [CFCDB]
A) Makes a service offering visible to all orgs in the marketplace B) Grants a user permission to bind a service C) Starts a stopped service instance D) Creates a new service plan Answer: A Explanation: cf enable-service-access publishes a service plan to the marketplace for orgs to use. Question 55. Which command can be used to view the current memory limit of an organization? A) cf org ORG_NAME – guid B) cf org ORG_NAME – quota C) cf quotas – org ORG_NAME D) cf org‑quota ORG_QUOTA_NAME Answer: B Explanation: cf org ORG_NAME --quota shows the quota details, including memory limits. Question 56. In Cloud Foundry, what is the purpose of the “router” component? A) Scheduling containers onto cells B) Managing user authentication C) Routing incoming HTTP/TCP traffic to app instances D) Storing application logs Answer: C Explanation: The Router directs external requests to the appropriate app instances based on routes. Question 57. Which of the following statements about Application Security Groups (ASGs) is true? A) ASGs define inbound network policies for apps B) ASGs are applied per organization, not per app C) ASGs control egress traffic from app containers D) ASGs replace service bindings for credential management Answer: C
Exam Preparation Guide [CFCDB]
Explanation: ASGs specify outbound (egress) network rules for app containers. Question 58. When an app crashes during staging, which command can help retrieve the detailed error output? A) cf logs APP – recent B) cf events APP C) cf staging‑logs APP D) cf restart APP – force Answer: A Explanation: Recent logs include staging output, which often contains the error details. Question 59. Which CLI flag sets the amount of disk space allocated to an app during push? A) – disk B) – disk-quota C) – d D) – space Answer: B Explanation: --disk-quota defines the per‑instance disk allocation. Question 60. What does the cf push option –no-start accomplish? A) Pushes the app but does not start any instances until a later cf start B) Skips the staging phase entirely C) Prevents route creation D) Disables health checks Answer: A Explanation: --no-start uploads and stages the app but leaves it in a stopped state. Question 61. Which command removes a route from an app without deleting the route itself? A) cf unmap-route APP DOMAIN – hostname HOST B) cf delete-route DOMAIN – hostname HOST C) cf unbind-route APP DOMAIN – hostname HOST
Exam Preparation Guide [CFCDB]
Question 65. Which of the following is a recommended practice for handling secrets in Cloud Foundry? A) Hard‑code credentials in source code B) Store secrets in VCAP_SERVICES via service bindings C) Place passwords in config files inside the app repository D) Use environment variables defined in the manifest only Answer: B Explanation: Using bound services to inject secrets via VCAP_SERVICES keeps credentials out of code. Question 66. Which command shows the current health check type of an app? A) cf health-check APP B) cf app APP – guid C) cf get-health-check APP D) cf app APP Answer: D Explanation: cf app APP lists app details, including the health check type. Question 67. When an app is scaled horizontally, which metric is most likely to increase proportionally? A) Total memory usage across the app B) Disk quota per instance C) Number of routes D) Instance GUID length Answer: A Explanation: Adding instances multiplies total memory consumption (instances × memory per instance). Question 68. Which component of Cloud Foundry is responsible for authenticating API requests? A) Router B) UAA (User Account and Authentication)
Exam Preparation Guide [CFCDB]
C) Loggregator D) Diego Brain Answer: B Explanation: UAA handles OAuth token issuance and validation for API calls. Question 69. What is the purpose of the “manifest.yml” file in a Cloud Foundry app? A) Define buildpack detection rules B) Specify deployment configuration such as memory, routes, and services C) Store application source code D) List all available services in the marketplace Answer: B Explanation: The manifest provides declarative configuration for cf push. Question 70. Which CLI option forces a zero‑downtime deployment by automatically mapping the new version’s route after staging? A) – strategy rolling B) – strategy blue-green C) – no-route D) – push‑new‑route Answer: B Explanation: --strategy blue-green orchestrates a zero‑downtime switch using route mapping. Question 71. In Cloud Foundry, what does the “instance index” represent? A) The order in which an instance was started B) A zero‑based identifier unique within the app’s instances C) The memory limit assigned to the instance D) The port number the instance listens on Answer: B Explanation: CF_INSTANCE_INDEX is a sequential number (0,1,2…) identifying each instance. Question 72. Which command displays the current quotas assigned to a space?
