Oracle 1Z0-1084-21 Online Practice Questions and Exam Preparation

Oracle 1Z0-1084-21 Online Questions & Answers

• Question 41:

  Which two are characteristics of microservices?

  A. Microservices are hard to test in isolation.
  B. Microservices can be independently deployed.
  C. All microservices share a data store.
  D. Microservices can be implemented in limited number of programming languages.
  E. Microservices communicate over lightweight APIs.
  B. Microservices can be independently deployed.
  E. Microservices communicate over lightweight APIs.

  ---

  https://www.techjini.com/blog/microservices/

• Question 42:

  Which pattern can help you minimize the probability of cascading failures in your system during partial loss of connectivity or a complete service failure?

  A. Retry pattern
  B. Anti-corruption layer pattern
  C. Circuit breaker pattern
  D. Compensating transaction pattern
  C. Circuit breaker pattern

  ---

  A cascading failure is a failure that grows over time as a result of positive feedback. It can occur when a portion of an overall system fails, increasing the probability that other portions of the system fail. the circuit breaker pattern prevents the service from performing an operation that is likely to fail. For example, a client service can use a circuit breaker to prevent further remote calls over the network when a downstream service is not functioning properly. This can also prevent the network from becoming congested by a sudden spike in failed retries by one service to another, and it can also prevent cascading failures. Self-healing circuit breakers check the downstream service at regular intervals and reset the circuit breaker when the downstream service starts functioning properly. https://blogs.oracle.com/developers/getting-started-with-microservices-part-three

• Question 43:

  What is the minimum of storage that a persistent volume claim can obtain in Oracle Cloud Infrastructure Container Engine for Kubernetes (OKE)?

  A. 50 GB
  B. 10 GB
  C. 1 GB
  D. 1 TB
  A. 50 GB

  ---

  The minimum amount of persistent storage that a PVC can request is 50 gigabytes. If the request is for less than 50 gigabytes, the request is rounded up to 50 gigabytes. https://docs.cloud.oracle.com/en-us/iaas/Content/ContEng/Tasks/contengcreatingpersistentvolumeclaim.htm

• Question 44:

  Which two statements are true for service choreography?

  A. Service choreographer is responsible for invoking other services.
  B. Services involved in choreography communicate through messages/messaging systems.
  C. Service choreography relies on a central coordinator.
  D. Service choreography should not use events for communication.
  E. Decision logic in service choreography is distributed.
  B. Services involved in choreography communicate through messages/messaging systems.
  E. Decision logic in service choreography is distributed.

  ---

  Service Choreography Service choreography is a global description of the participating services, which is defined by exchange of messages, rules of interaction and agreements between two or more endpoints. Choreography employs a decentralized approach for service composition. the decision logic is distributed, with no centralized point.

  

  Choreography, in contrast, does not rely on a central coordinator. and all participants in the choreography need to be aware of the business process, operations to execute, messages to exchange, and the timing of message exchanges.

• Question 45:

  With the volume of communication that can happen between different components in cloud-native applications, it is vital to not only test functionality, but also service resiliency. Which statement is true with regards to service resiliency?

  A. Resiliency is about recovering from failures without downtime or data loss.
  B. A goal of resiliency is not to bring a service to a functioning state after a failure.
  C. Resiliency testing can be only done in a test environment.
  D. Resiliency is about avoiding failures.
  D. Resiliency is about avoiding failures.

  ---

  Resiliency and Availability

  Resiliency and availability refers to the ability of a system to continue operating, despite the failure or sub-optimal performance of some of its components.

  In the case of Oracle Functions:

  The control plane is a set of components that manages function definitions. The data plane is a set of components that executes functions in response to invocation requests. For resiliency and high availability, both the control plane and data plane components are distributed across different availability domains and fault domains in a region. If one of the domains ceases to be available, the components in the remaining domains take over to ensure that function definition management and execution are not disrupted. When functions are invoked, they run in the subnets specified for the application to which the functions belong. For resiliency and high availability, best practice is to specify a regional subnet for an application (or alternatively, multiple AD-specific subnets in different availability domains). If an availability domain specified for an application ceases to be available, Oracle Functions runs functions in an alternative availability domain.

• Question 46:

  You are developing a polyglot serverless application using Oracle Functions. Which language cannot be used to write your function code?

  A. PL/SQL
  B. Python
  C. Node.js
  D. Java
  A. PL/SQL

  ---

  The serverless and elastic architecture of Oracle Functions means there's no infrastructure administration or software administration for you to perform. You don't provision or maintain compute instances, and operating system software patches and upgrades are applied automatically. Oracle Functions simply ensures your app is highly-available, scalable, secure, and monitored. With Oracle Functions, you can write code in Java, Python, Node, Go, and Ruby (and for advanced use cases, bring your own Dockerfile, and Graal VM). You can then deploy your code, call it directly or trigger it in response to events, and get billed only for the resources consumed during the execution.

• Question 47:

  You are processing millions of files in an Oracle Cloud Infrastructure (OCI) Object Storage bucket. Each time a new file is created, you want to send an email to the customer and create an order in a database. The solution should perform and minimize cost, Which action should you use to trigger this email?

  A. Schedule a cron job that monitors the OCI Object Storage bucket and emails the customer when a new file is created.
  B. Use OCI Events service and OCI Notification service to send an email each time a file is created.
  C. Schedule an Oracle Function that checks the OCI Object Storage bucket every minute and emails the customer when a file is found.
  D. Schedule an Oracle Function that checks the OCI Object Storage bucket every second and emails the customer when a file is found.
  B. Use OCI Events service and OCI Notification service to send an email each time a file is created.

  ---

  Oracle Cloud Infrastructure Events enables you to create automation based on the state changes of resources throughout your tenancy. Use Events to allow your development teams to automatically respond when a resource changes its state. Here are some examples of how you might use Events: Send a notification to a DevOps team when a database backup completes. Convert files of one format to another when files are uploaded to an Object Storage bucket. You can only deliver events to certain Oracle Cloud Infrastructure services with a rule. Use the following services to create actions: Notifications Streaming Functions

  

• Question 48:

  Which two statements are true for serverless computing and serverless architectures?

  A. Long running tasks are perfectly suited for serverless
  B. Serverless function state should never be stored externally
  C. Application DevOps team is responsible for scaling
  D. Serverless function execution is fully managed by a third party
  E. Applications running on a FaaS (Functions as a Service) platform
  B. Serverless function state should never be stored externally
  E. Applications running on a FaaS (Functions as a Service) platform

  ---

  Oracle Functions is a fully managed, multi-tenant, highly scalable, on-demand, Functions-as-a- Service platform. It is built on enterprise-grade Oracle Cloud Infrastructure and powered by the Fn Project open source engine. Use Oracle Functions (sometimes abbreviated to just Functions) when you want to focus on writing code to meet business needs. The serverless and elastic architecture of Oracle Functions means there's no infrastructure administration or software administration for you to perform. You don't provision or maintain compute instances, and operating system software patches and upgrades are applied automatically. Oracle Functions simply ensures your app is highly-available, scalable, secure, and monitored Applications built with a serverless infrastructure will scale automatically as the user base grows or usage increases. If a function needs to be run in multiple instances, the vendor's servers will start up, run, and end them as they are needed. Oracle Functions is based on Fn Project. Fn Project is an open source, container native, serverless platform that can be run anywhere - any cloud or on-premises. Serverless architectures are not built for long-running processes. This limits the kinds of applications that can cost-effectively run in a serverless architecture. Because serverless providers charge for the amount of time code is running, it may cost more to run an application with long-running processes in a serverless infrastructure compared to a traditional one.

  https://docs.cloud.oracle.com/en-us/iaas/Content/Functions/Concepts/functionsconcepts.htm https://www.cloudflare.com/learning/serverless/why-use-serverless/

• Question 49:

  As a cloud-native developer, you have written a web service for your company. You have used Oracle Cloud Infrastructure (OCI) API Gateway service to expose the HTTP backend. However, your security team has suggested that your web

  service should handle Distributed Denial-of-Service (DDoS) attack. You are time-constrained and you need to make sure that this is implemented as soon as possible.

  What should you do in this scenario?

  A. Use OCI virtual cloud network (VCN) segregation to control DDoS.
  B. Use a third party service integration to implement a DDoS attack mitigation,
  C. Use OCI API Gateway service and configure rate limiting.
  D. Re-write your web service and implement rate limiting.
  C. Use OCI API Gateway service and configure rate limiting.

  ---

  Having created an API gateway and deployed one or more APIs on it, you'll typically want to limit the rate at which front-end clients can make requests to back-end services. For example, to:

  - maintain high availability and fair use of resources by protecting back ends from being overwhelmed by too many requests

  -prevent denial-of-service attacks

  -constrain costs of resource consumption

  - restrict usage of APIs by your customers' users in order to monetize APIs You apply a rate limit globally to all routes in an API deployment specification. If a request is denied because the rate limit has been exceeded, the response header

  specifies when the request can be retried.

  You can add a rate-limiting request policy to an API deployment specification by:

  using the Console editing a JSON file

• Question 50:

  You have written a Node.js function and deployed it to Oracle Functions. Next, you need to call this function from a microservice written in Java deployed on Oracle Cloud Infrastructure (OCI) Container Engine for Kubernetes (OKE). Which can help you to achieve this?

  A. Use the OCI CLI with kubect1 to invoke the function from the microservice.
  B. Oracle Functions does not allow a microservice deployed on OKE to invoke a function.
  C. OKE does not allow a microservice to invoke a function from Oracle Functions.
  D. Use the OCI Java SDK to invoke the function from the microservice.
  D. Use the OCI Java SDK to invoke the function from the microservice.

  ---

  You can invoke a function that you've deployed to Oracle Functions in different ways:

  Using the Fn Project CLI.

  Using the Oracle Cloud Infrastructure CLI.

  Using the Oracle Cloud Infrastructure SDKs.

  Making a signed HTTP request to the function's invoke endpoint. Every function has an invoke endpoint.