ENH: Added load balancing application in terraform

terraform_provisioning/README.md

@@ -2,6 +2,31 @@
 * This folder contains terraform scripts to manage openstack configurations
 * These require a `clouds.yaml` in `~/.config/openstack/` to provide authentication
 
+## Running the scripts
+* The scripts require the terraform package to be installed
+    * To install terraform on ubuntu or any ubuntu derivative with snap installed:
+```bash
+snap install terraform --classic
+```
+* If you are confused please find further info [here](https://developer.hashicorp.com/terraform/tutorials/aws-get-started/install-cli)
+* To actually run the script, start by entering the directory of the script you want to run, e.g.:
+```bash
+cd load_balancing_application
+```
+* Then generate a plan, this will also tell you what actions terraform will perform:
+    * Note this will generate a plan file in the current directory
+```bash
+terraform plan -out plan --var-file=vars.tfvars
+```
+* After that, to actually "apply" the changes planned in the plan:
+```bash
+terraform apply plan
+```
+* To revert the changes, e.g. to change the number of instances, use:
+```bash
+terraform destroy --var-file=vars.tfvars
+```
+
 ## private_network
 * This terraform script creates a private network with a subnet domain of `10.0.0.x`
 * It also adds a router to connect the private network to the external network

terraform_provisioning/load_balancing_application/load_balancing_application.tf → terraform_provisioning/load_balancing_application/deploy.tf

@@ -16,22 +16,22 @@ provider "openstack" {
 
 # Creates a private network
 resource "openstack_networking_network_v2" "private_network" {
-  name           = "private_network"
+  name           = "${var.deployment_name}-private_network"
   admin_state_up = "true"
 }
 
 # Creates a subnet within our private network 
 resource "openstack_networking_subnet_v2" "subnet" {
-  name       = "subnet"
+  name       = "${var.deployment_name}-subnet"
   network_id = openstack_networking_network_v2.private_network.id
-  cidr       = "192.168.3.0/24"
+  cidr       = "192.168.1.0/24"
   ip_version = 4
 }
 
 # Creates a router within our network
 resource "openstack_networking_router_v2" "router" {
   name                = "${var.deployment_name}-router"
-  external_network_id = var.external
+  external_network_id = var.external_network_id
 }
 
 # Connects the router to our subnet
@@ -42,17 +42,17 @@ resource "openstack_networking_router_interface_v2" "router_interface" {
 
 # Create a load balancer and places it in the subnet we made earlier
 resource "openstack_lb_loadbalancer_v2" "loadbalancer" {
-  name = "loadbalancer"
+  name = "${var.deployment_name}-loadbalancer"
   vip_subnet_id = openstack_networking_subnet_v2.subnet.id
   vip_address = var.floating_ip
 }
 
 # Creating the bastion vm to access the other vm's
 resource "openstack_compute_instance_v2" "bastion" {
+  name = "${var.deployment_name}-bastion"
   image_name = var.image_name
   flavor_name = var.flavor_name
   key_pair = var.key_pair
-  name = "bastion"
 
   network {
     uuid = openstack_networking_network_v2.private_network.id
@@ -61,7 +61,7 @@ resource "openstack_compute_instance_v2" "bastion" {
 
 # Create a ssh listener for the bastion vm
 resource "openstack_lb_listener_v2" "ssh_listener" {
-  name = "bastion-ssh"
+  name = "${var.deployment_name}-bastion-ssh"
   protocol        = "TCP"
   protocol_port   = 22
   loadbalancer_id = openstack_lb_loadbalancer_v2.loadbalancer.id
@@ -72,23 +72,23 @@ resource "openstack_lb_listener_v2" "ssh_listener" {
 
 # Create an ssh listener for the web servers
 resource "openstack_lb_listener_v2" "web_server_listener" {
-  name = "web_servers"
+  name = "${var.deployment_name}-web_servers"
   protocol        = "TCP"
   protocol_port   = 80 
   loadbalancer_id = openstack_lb_loadbalancer_v2.loadbalancer.id
 }
 
 # Creating the ssh pool
 resource "openstack_lb_pool_v2" "ssh_pool" {
-  name = "ssh-pool"
+  name = "${var.deployment_name}-ssh-pool"
   protocol    = "TCP"
   lb_method   = "SOURCE_IP"
   listener_id = openstack_lb_listener_v2.ssh_listener.id
 }
 
 # Creating a web_servers pool
 resource "openstack_lb_pool_v2" "web_servers_pool" {
-  name = "web_servers_pool"
+  name = "${var.deployment_name}-web_servers_pool"
   protocol    = "TCP"
   lb_method   = "SOURCE_IP"
   listener_id = openstack_lb_listener_v2.web_server_listener.id
@@ -112,11 +112,11 @@ resource "openstack_lb_member_v2" "web_server_member" {
 
 # Create multiple vm's for web serving
 resource "openstack_compute_instance_v2" "vm" {
+  name = format("${var.deployment_name}-vm-%d", count.index)
   count = var.instances
   image_name = var.image_name
   flavor_name = var.flavor_name
   key_pair = var.key_pair 
-  name = format("vm-%d", count.index)
 
   network {
     uuid = openstack_networking_network_v2.private_network.id

terraform_provisioning/load_balancing_application/variables.tf

@@ -1,13 +1,13 @@
-variable "external" {
-  description = "The id of the external network to connect the router to"
-  type = string 
-}
-
 variable "deployment_name" {
-  description = "The name of the deployment (prepended to router name)"
+  description = "The name of the deployment (prepended to things)"
   type = string
 }
 
+variable "external_network_id" {
+  description = "The id of the external network to connect the router to"
+  type = string 
+}
+
 variable "floating_ip" {
   description = "The floating ip to attach to the load balancer to access the grafanas"
   type = string

terraform_provisioning/load_balancing_application/vars.tfvars

@@ -1,7 +1,7 @@
-external = ""
 deployment_name = ""
+external_network_id = ""
 floating_ip = ""
-image_name = "ubuntu-focal-20.04-nogui"
-flavor_name = "l3.nano"
+image_name = ""
+flavor_name = ""
 key_pair = ""
-instances = 1 
+instances =