nat.tf

# Nat gateway #1
resource "aws_eip" "nat_1" {
  count = "${local.nat_gw ? 1 : 0}"
}
resource "aws_nat_gateway" "nat_1" {
  count = "${local.nat_gw ? 1 : 0}"
  allocation_id = "${aws_eip.nat_1.id}"
  subnet_id = "${aws_subnet.public_nat_1.id}"
}

# Nat gateway #2
resource "aws_eip" "nat_2" {
  count = "${local.nat_gw_multi_az ? 1 : 0}"
}
resource "aws_nat_gateway" "nat_2" {
  count = "${local.nat_gw_multi_az ? 1 : 0}"

  allocation_id = "${aws_eip.nat_2.id}"
  subnet_id = "${aws_subnet.public_nat_2.id}"
}

// aws --region eu-west-1 ec2 describe-images --owners amazon --filters Name="name",Values="amzn-ami-vpc-nat*"
data "aws_ami" "nat" {
  most_recent = true

  filter {
    name   = "name"
    values = ["amzn-ami-vpc-nat*"]
  }

  owners = ["amazon"]
}

# Nat instance #1
resource "aws_instance" "nat_1" {
  count                       = "${local.nat_instance ? 1 : 0}"
  ami                         = "${data.aws_ami.nat.id}"
  instance_type               = "${var.nat_instance_type}"
  source_dest_check           = false
  subnet_id                   = "${aws_subnet.public_nat_1.id}"
  associate_public_ip_address = true
  vpc_security_group_ids      = ["${aws_security_group.access_via_nat.id}"]

  tags {
    Name = "NAT #1"
  }
}

# Nat instance #2
resource "aws_instance" "nat_2" {
  count                       = "${local.nat_instance_multi_az ? 1 : 0}"
  ami                         = "${data.aws_ami.nat.id}"
  instance_type               = "${var.nat_instance_type}"
  source_dest_check           = false
  subnet_id                   = "${aws_subnet.public_nat_2.id}"
  associate_public_ip_address = true
  vpc_security_group_ids      = ["${aws_security_group.access_via_nat.id}"]

  tags {
    Name = "NAT #2"
  }
}