[KingOfCoders]

I basically have no clue.

I thought one would have a node two VPC, e.g. app and database, so it can speak to both, but the load balancers can't.

With peering one would have an app VPC and a database VPC and peer them?

[vorpalhex]

In AWS you use a mix of private and public subnets within a single VPC.

Not sure best practice for DO since I haven't tried their VPC setup but it doesn't appear to have a way to let two VPCs interact yet.