aws: Add each test instance to the local DNS service

The kdevops NFS workflows typically set up separate nodes for an NFS
server and NFS clients. kdevops then provisions exports on the NFS
server and mount points on the clients.

For libvirt, kdevops adds the IP address of each test node to all of
the /etc/hosts files. This enables the clients to mount the test NFS
server conveniently by hostname.

For AWS, kdevops can provision a private DNS service and add "A"
records for each test host there. This patch implements that
approach.

Tested-by: Luis Chamberlain <[email protected]>
Signed-off-by: Chuck Lever <[email protected]>

terraform/aws/main.tf

@@ -184,3 +184,33 @@ resource "aws_route_table_association" "kdevops_rt_assoc" {
   route_table_id = aws_route_table.kdevops_rt.id
 }
 
+resource "aws_vpc_dhcp_options" "kdevops_dhcp_opts" {
+  domain_name         = "kdevops.local"
+  domain_name_servers = ["AmazonProvidedDNS"]
+
+  tags = {
+    Name = "kdevops_dhcp_opts"
+  }
+}
+
+resource "aws_vpc_dhcp_options_association" "kdevops_dhcp_association" {
+  vpc_id          = aws_vpc.kdevops_vpc.id
+  dhcp_options_id = aws_vpc_dhcp_options.kdevops_dhcp_opts.id
+}
+
+resource "aws_route53_zone" "kdevops_private_zone" {
+  name = "kdevops.local"
+  vpc {
+    vpc_id = aws_vpc.kdevops_vpc.id
+  }
+}
+
+resource "aws_route53_record" "kdevops_dns_record" {
+  count   = local.kdevops_num_boxes
+  zone_id = aws_route53_zone.kdevops_private_zone.zone_id
+  name    = "${element(var.kdevops_nodes, count.index)}.kdevops.local"
+  type    = "A"
+  ttl     = "300"
+  records = ["${element(aws_instance.kdevops_instance.*.private_ip, count.index)}"]
+}
+