Binding a service instance to a Cloud Foundry app using the IBM Cloud CLI (e.g., `ibmcloud cf bind-service`) is the standard, secure, and IBM-recommended practice. It automatically injects the service credentials into the application’s environment as the VCAP_SERVICES variable, eliminating hardcoded secrets and simplifying credential management across different environments (dev, staging, prod).

IBM Event Streams is a high-throughput, fault-tolerant, Apache Kafka-based event streaming platform. It is specifically designed for building real-time data pipelines and streaming applications, making it ideal for ingesting and processing high-volume IoT sensor data with low latency, which is a core requirement for immediate alerting systems.

Resizing worker nodes to a smaller, more appropriate flavor (e.g., using the `ibmcloud ks worker replace` command) is a direct and effective way to reduce costs when nodes are persistently underutilized. It addresses the root cause (over-provisioned resources) while maintaining the same number of nodes for pod scheduling capacity. Cluster autoscaler (option D) is also a good practice but is more about dynamic adjustment based on pending pods, not necessarily correcting a baseline of oversized nodes.

IBM Cloud Log Analysis’s archiving feature is designed for this exact purpose. It automatically forwards log data to a user-managed Cloud Object Storage bucket. Object Storage offers durable, scalable, and significantly more cost-effective storage for long-term retention (like seven years) compared to keeping all data in the active, searchable log database, which is priced for shorter-term analysis.

An IBM Cloud Load Balancer for VPC is a regional service that distributes traffic among backend targets (like VSI instances) across multiple zones. It provides a single public or private endpoint for clients, ensures high availability by checking instance health, and is the essential component for creating a cross-zone, highly available application architecture in VPC.

Using a Service ID with an associated API key is the IBM Cloud best practice for service-to-service authentication. It creates a non-human, machine identity for the application, allowing for fine-grained, least-privilege access policies. This is more secure and manageable than using a personal user’s API key (which ties access to an individual) or any form of hardcoded user credentials.

For an existing IBM Db2 on Cloud instance, enabling the BYOK/KYOK feature is the direct method to achieve encryption at rest. This feature integrates with IBM Cloud Key Protect or Hyper Protect Crypto Services to manage the encryption keys. It encrypts the underlying storage (including backups) without requiring changes to the database schema or the application code, which options A and D would necessitate.

IBM Cloud Code Engine allows you to configure a ‘Retry limit’ for jobs. If a job’s execution fails (returns a non-zero exit code), Code Engine can automatically retry it up to the specified limit. This built-in feature is perfect for handling transient errors like network timeouts, making the job more resilient without the need to implement retry logic within the job’s application code itself.

The correct IaC workflow with Schematics (and Terraform in general) is to update the source code (Terraform templates), then use the tool to generate an execution plan. In Schematics, this means updating your Git repo, then using the workspace’s ‘Plan’ action to preview the changes (showing only the new load balancer will be created). After reviewing, you ‘Apply’ the plan. This ensures state is managed correctly and the infrastructure is updated declaratively.

Binding a service instance to a Cloud Foundry app using the IBM Cloud CLI (e.g., `ibmcloud cf bind-service`) is the standard, secure, and IBM-recommended practice. It automatically injects the service credentials into the application’s environment as the VCAP_SERVICES variable, eliminating hardcoded secrets and simplifying credential management across different environments (dev, staging, prod).0