The correct answer is: fn deploy --app travel-app --all Explanation:: To build and deploy multiple Oracle Functions as part of a single application named 'travel-app,' you can use the fn deploy command with the appropriate options. The command fn deploy --app travel-app --all is the correct syntax. Here's what each part of the command does: fn deploy: This command is used to deploy functions and applications in Oracle Functions. --app travel-app: This option specifies the application name as 'travel-app,' indicating that you want to deploy functions to this application. --all: This option indicates that you want to deploy all the functions within the application. By using fn deploy --app travel-app --all, you can build and deploy all the functions in your travel application across different programming languages (Java, Python, and Node.js) to the 'travel-app' application in Oracle Functions.

The correct answer is: 'Once rotated, older key versions can be used for encryption until they are deleted.' The statement that is NOT valid about rotating keys in the OCI Vault service is: 'Once rotated, older key versions can be used for encryption until they are deleted.' In the OCI Vault service, when you rotate a master encryption key (MEK), a new key version is automatically generated. However, once a key is rotated and a new version is created, the older key versions are no longer usable for encryption. The purpose of key rotation is to ensure that the encryption keys are regularly updated and that older keys are no longer used to protect sensitive data. This enhances security by minimizing the impact of potential key compromises. The other statements mentioned are valid: Both software and hardware security module (HSM)-protected MEKs can be rotated. This provides flexibility in choosing the type of MEK and ensures that key rotation can be performed regardless of the encryption method used. Each key version is tracked internally with separate unique OCIDs (Oracle Cloud Identifiers). This allows for easy management and tracking of different key versions within the OCI Vault service. In summary, the statement that is NOT valid is the one suggesting that older key versions can still be used for encryption until they are deleted. Key rotation is designed to ensure the use of the latest key version and to retire older key versions to enhance security.

An Ingress Controller is a Kubernetes resource that provides advanced routing and load balancing for your applications running on a Kubernetes cluster1.An Ingress Controller allows you to define rules that specify how to route traffic to different services in your cluster based on the host name or path of the incoming request1.By deploying an Ingress Controller and using it to expose multiple application endpoints, you can achieve the following benefits1:

Cost-effectiveness: You only need to create one load balancer instance per cluster, instead of one per service, which reduces the cost of exposing your applications.

Simplicity: You only need to manage one set of routing rules for all your services, instead of configuring each service separately, which simplifies the application deployment and maintenance.

Flexibility: You can use different types of Ingress Controllers, such as NGINX or Traefik, that offer various features and customization options for your routing needs.

The correct API method to read and process a stream in the Oracle Cloud Infrastructure (OCI) Streaming service is 'GetMessages'. When consuming messages from a stream in OCI Streaming, you use the 'GetMessages' API method. This method allows you to retrieve a batch of messages from the stream for processing. You can specify parameters such as the number of messages to retrieve, the maximum size of the messages, and the timeout for the request. By using the 'GetMessages' API method, you can retrieve messages from the stream and then process them in your microservices application. This allows you to consume and handle the data in real-time as it becomes available in the stream. The 'GetMessages' method provides flexibility in how you consume and process the messages, enabling you to implement custom logic and workflows based on your specific application requirements.

Oracle Cloud Infrastructure (OCI) API Gateway supports various backend-types to handle incoming requests and route them to the appropriate backend service. However, 'ORACLE_STREAMS_BACKEND' is not a valid backend-type in OCI API Gateway. 'STOCK_RESPONSE_BACKEND' is a valid backend-type that allows you to configure static responses directly in the API Gateway without routing requests to any specific backend service. This can be useful for handling simple requests or returning predefined responses. 'HTTP BACKEND' is another valid backend-type that enables routing requests to an HTTP backend service. 'ORACLE_FUNCTIONS_BACKEND' is a valid backend-type that allows you to route requests to Oracle Functions, which are serverless functions that can be used to execute specific logic or operations. However, 'ORACLE_STREAMS_BACKEND' is not a valid backend-type in OCI API Gateway. The API Gateway does not have native support for Oracle Streams as a backend service. Oracle Streams is a feature of Oracle Database that provides a publish-subscribe mechanism for data replication and distribution within an Oracle Database environment. It is not directly integrated as a backend service in OCI API Gateway.