Creating AWS DocumentDB in non-default VPC

Question

I am struggling with setting up an AWS DocumentDB cluster in a non-default VPC. I created a new VPC with 1 public and 3 private subnets. The 3 private subnets are all in different Availability Zones and are grouped in one Subnet Group. Still, I can only select the default VPC when I try to create a new DocumentDB cluster. Am I missing something? As far as I can tell I am meeting all VPC requirements that are listed in the official docs: https://docs.aws.amazon.com/documentdb/latest/developerguide/db-cluster-create.html

Answer 1

I found the solution: seems like AWS is using the term "Subnet Group" in multiple services. I created the group in the service "ElastiCache" but it needs to be created in service "DocumentDB" (see screenshot below).