From 5429f6aeb9b58a35c9b9617bddbdbc1ab4f6f905 Mon Sep 17 00:00:00 2001
From: Alex Chan <alex@alexwlchan.net>
Date: Mon, 6 Jul 2020 14:55:51 +0100
Subject: [PATCH] docs/rds_cluster_instance: the engine/version should match
 that of the cluster (#14037)

If you try to create an RDS instance with a different engine/version to
the cluster, you get an InvalidParameterCombination error from Terraform
and no instances.

Changing the behaviour so that instances inherit their config from the
cluster is a big change.

This patch just tweaks the documented examples, so if people copy/paste
the example and change the engine/version of the cluster, it will still
work correctly.  It also highlights that the engine/version should
match between the instance and the cluster.

Relates to https://github.com/terraform-providers/terraform-provider-aws/issues/10585
---
 website/docs/r/rds_cluster_endpoint.html.markdown | 6 ++++++
 website/docs/r/rds_cluster_instance.html.markdown | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/website/docs/r/rds_cluster_endpoint.html.markdown b/website/docs/r/rds_cluster_endpoint.html.markdown
index 93341770551..742052046cf 100644
--- a/website/docs/r/rds_cluster_endpoint.html.markdown
+++ b/website/docs/r/rds_cluster_endpoint.html.markdown
@@ -30,6 +30,8 @@ resource "aws_rds_cluster_instance" "test1" {
   cluster_identifier = "${aws_rds_cluster.default.id}"
   identifier         = "test1"
   instance_class     = "db.t2.small"
+  engine             = "${aws_rds_cluster.default.engine}"
+  engine_version     = "${aws_rds_cluster.default.engine_version}"
 }
 
 resource "aws_rds_cluster_instance" "test2" {
@@ -37,6 +39,8 @@ resource "aws_rds_cluster_instance" "test2" {
   cluster_identifier = "${aws_rds_cluster.default.id}"
   identifier         = "test2"
   instance_class     = "db.t2.small"
+  engine             = "${aws_rds_cluster.default.engine}"
+  engine_version     = "${aws_rds_cluster.default.engine_version}"
 }
 
 resource "aws_rds_cluster_instance" "test3" {
@@ -44,6 +48,8 @@ resource "aws_rds_cluster_instance" "test3" {
   cluster_identifier = "${aws_rds_cluster.default.id}"
   identifier         = "test3"
   instance_class     = "db.t2.small"
+  engine             = "${aws_rds_cluster.default.engine}"
+  engine_version     = "${aws_rds_cluster.default.engine_version}"
 }
 
 resource "aws_rds_cluster_endpoint" "eligible" {
diff --git a/website/docs/r/rds_cluster_instance.html.markdown b/website/docs/r/rds_cluster_instance.html.markdown
index 125b24498bb..0c530918701 100644
--- a/website/docs/r/rds_cluster_instance.html.markdown
+++ b/website/docs/r/rds_cluster_instance.html.markdown
@@ -31,6 +31,8 @@ resource "aws_rds_cluster_instance" "cluster_instances" {
   identifier         = "aurora-cluster-demo-${count.index}"
   cluster_identifier = "${aws_rds_cluster.default.id}"
   instance_class     = "db.r4.large"
+  engine             = "${aws_rds_cluster.default.engine}"
+  engine_version     = "${aws_rds_cluster.default.engine_version}"
 }
 
 resource "aws_rds_cluster" "default" {