Terraform Data Sources: How to Deploy EC2 Without Hardcoding IDs

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A Terraform tutorial published on DEV Community demonstrates how to deploy EC2 instances into an existing VPC and subnet using data sources instead of hardcoded resource IDs. The guide walks through referencing a pre-existing VPC, subnet, and the latest Amazon Linux 2 AMI dynamically via Terraform's data blocks. By filtering resources using name tags and owner metadata, the configuration avoids manual ID management and reduces human error. This approach promotes reusability, as shared network infrastructure managed by other teams can be referenced without being recreated. The method also ensures EC2 instances always launch with the most recent AMI, improving reliability and scalability across environments.

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