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Terraform: Providing Multiple Security Groups to an EC2 Instance Using Dynamic Blocks

👀 Views: 0 💬 Answers: 1 📅 Created: 2025-06-12
terraform aws ec2 dynamic-blocks HCL

I've hit a wall trying to I'm trying to create an EC2 instance in AWS using Terraform, and I want to attach multiple security groups to it. I came across dynamic blocks in Terraform, but despite configuring them, I'm working with issues with getting the security groups applied correctly. Here's a snippet of my code: ```hcl variable "security_groups" { type = list(string) } resource "aws_instance" "example" { ami = "ami-0c55b159cbfafe1f0" instance_type = "t2.micro" dynamic "vpc_security_group_ids" { for_each = var.security_groups content { vpc_security_group_id = vpc_security_group_ids.value } } } ``` I am passing a list of security group IDs to the `security_groups` variable but keep getting the following behavior when I run `terraform apply`: ``` behavior: Invalid function argument on main.tf line XX, in resource "aws_instance" "example": XX: vpc_security_group_id = vpc_security_group_ids.value This value does not have any attributes. ``` I’ve tried changing the `for_each` to `for` but that didn't work either. I've also ensured that the security group IDs are valid and exist in the specified region. Can someone clarify how to properly use dynamic blocks for security groups in this context? Is there a better way to handle multiple security groups without running into this scenario? Any advice would be greatly appreciated! Thanks for any help you can provide!