A "Layer" is a particular service that forms part of the infrastructure for
a set of applications. Some layers are application servers and others are
pure infrastructure, like MySQL servers or load balancers.
Although the AWS API only has one type called "Layer", it actually has
a number of different "soft" types that each have slightly different
validation rules and extra properties that are packed into the Attributes
map.
To make the validation rule differences explicit in Terraform, and to make
the Terraform structure more closely resemble the OpsWorks UI than its
API, we use a separate resource type per layer type, with the common code
factored out into a shared struct type.
"Stack" is the root concept in OpsWorks, and acts as a container for a number
of different "layers" that each provide some service for an application.
A stack isn't very interesting on its own, but it needs to be created before
any layers can be created.
For those accustomed to running commands via a shell it may not be clear
why this argument is a list and what the elements of that list should be.
Hopefully giving an example will help people understand what is expected.
This is in response to the misunderstanding discovered in #3011.
An earlier version of the provider implementation accepted
key_material_file instead of key_material. This was updated in the
resource-specific docs but not in this provider-wide example.
* 'master' of github.com:hashicorp/terraform:
Update CHANGELOG.md
Changing the ElastiCache Cluster configuration_engine to be on the cluster, not on the cache nodes
Adding configuration endpoint to the elasticache cluster nodes
When launching a new RDS instance in a VPC-default AWS account, trying to control which VPC the new RDS instance lands in is not apparent from the parameters available.
The following works:
```
resource "aws_db_subnet_group" "foo" {
name = "foo"
description = "DB Subnet for foo"
subnet_ids = ["${aws_subnet.foo_1a.id}", "${aws_subnet.foo_1b.id}"]
}
resource "aws_db_instance" "bar" {
...
db_subnet_group_name = "${aws_db_subnet_group.foo.name}"
...
}
```
Hopefully this doc update will help others
