Azure Infrastructure Automation with Terraform ( Part 4)

We are going to create an Inbound NAT Rule for Standard Load Balancer.

1. azurerm_lb_nat_rule

2. azurerm_network_interface_nat_rule_association

3. Verify the SSH Connectivity to Web Linux VM using Load Balancer Public IP with port 1022

Steps:

1. Create File: 9_04_web_loadbalancer_inbound_nat_rules.tf

   

    # Azure LoadBalancer Inbound NAT Rule
   
    resource "azurerm_lb_nat_rule" "web_lb_inbound_nat_rule_22" {
      resource_group_name            = azurerm_resource_group.rg.name
      name                           = "ssh-1022-vm-22"
      protocol                       = "Tcp"
      frontend_port                  = 1022
      backend_port                   = 22
      frontend_ip_configuration_name = azurerm_lb.web_lb.frontend_ip_configuration[0].name  
      loadbalancer_id                = azurerm_lb.web_lb.id
    }
   
    # Associate LoadBalancer NAT Rule and VM Network Interface
    resource "azurerm_network_interface_nat_rule_association" "web_nic_nat_rule_associate" {
      network_interface_id  = azurerm_network_interface.web_linuxvm_nic.id
      ip_configuration_name = azurerm_network_interface.web_linuxvm_nic.ip_configuration[0].name 
      nat_rule_id           = azurerm_lb_nat_rule.web_lb_inbound_nat_rule_22.id
    }
   

2. Execute Terraform Commands

    # Terraform Initialize
    terraform init
   
    # Terraform Validate
    terraform validate
   
    # Terraform Plan
    terraform plan
   
    # Terraform Apply
    terraform apply -auto-approve
   

   

   

   

   

   

3. Verify Resources

    # Verify Resources - Virtual Network
    1. Azure Resource Group
    2. Azure Virtual Network
    3. Azure Subnets (Web, App, DB, Bastion)
    4. Azure Network Security Groups (Web, App, DB, Bastion)
    5. View the topology
    6. Verify Terraform Outputs in Terraform CLI
   
    # Verify Resources - Web Linux VM 
    1. Verify Network Interface created for Web Linux VM
    2. Verify Web Linux VM
    3. Verify Network Security Groups associated with VM (web Subnet NSG)
    4. View Topology at Web Linux VM -> Networking
    5. Verify if only private IP associated with Web Linux VM
   
    # Verify Resources - Bastion Host
    1. Verify Bastion Host VM Public IP
    2. Verify Bastion Host VM Network Interface
    3. Verify Bastion VM
    4. Verify Bastion VM -> Networking -> NSG Rules
    5. Verify Bastion VM Topology
   
    # Connect to Bastion Host VM
    1. Connect to Bastion Host Linux VM
    ssh -i ssh-keys/terraform-azure.pem azureuser@<Bastion-Host-LinuxVM-PublicIP>
    sudo su - 
    cd /tmp
    ls 
    2. terraform-azure.pem file should be present in /tmp directory
   
    # Connect to Web Linux VM using Bastion Host VM
    1. Connect to Web Linux VM
    ssh -i ssh-keys/terraform-azure.pem azureuser@<Web-LinuxVM-PrivateIP>
    sudo su - 
    cd /var/log
    tail -100f cloud-init-output.log
    cd /var/www/html
    ls -lrt
    cd /var/www/html/app1
    ls -lrt
    exit
    exit
   
    # Verify Standard Load Balancer Resources
    1. Verify Public IP Address for Standard Load Balancer
    2. Verify Standard Load Balancer (SLB) Resource
    3. Verify SLB - Frontend IP Configuration
    4. Verify SLB - Backend Pools
    5. Verify SLB - Health Probes
    6. Verify SLB - Load Balancing Rules
    7. Verify SLB - Insights
    8. Verify SLB - Diagnose and Solve Problems
   
    # Access Application
    http://<LB-Public-IP>
    http://<LB-Public-IP>/app1/index.html
    http://<LB-Public-IP>/app1/metadata.html
   

   

   

4. Verify Inbound NAT Rules for Port 22

5. Delete Resources

    # Delete Resources
    terraform destroy 
    [or]
    terraform apply -destroy -auto-approve
   
    # Clean-Up Files
    rm -rf .terraform* 
    rm -rf terraform.tfstate*
   

   

Creation of Inbound Nat Rules for load balancer is implemented and in the next blog, we will see the same thing for multiple VMs using meta argument count.

Github:
https://github.com/DeoreRohit4/Azure-Infrastructure-Automation-with-Terraform-

Part 1: https://rohitexplainstech.hashnode.dev/azure-infrastructure-automation-with-terraform
Part 2: https://rohitexplainstech.hashnode.dev/azure-infrastructure-automation-with-terraform-part-2
Part 3: https://rohitexplainstech.hashnode.dev/azure-infrastructure-automation-with-terraform-part-3

---

Keep Exploring...