Terraform Workspaces with Local Backend

Step-01: Introduction¶

We are going to use Terraform Local Backend
We are going to create 2 workspaces (default, dev) in addition to default workspace
Update our terraform manifests to support terraform workspace
Master the below listed terraform workspace commands
terraform workspace show
terraform workspace list
terraform workspace new
terraform workspace select
terraform workspace delete

Step-02: Review Terraform Configs and make changes¶

Copy terraform-manifests from 38-Terraform-Remote-State-Storage-and-Locking and make following changes

Step-03: c1-versions.tf¶

Remove Backend block from Terraform Settings block if any present

# Terraform State Storage to Azure Storage Container
  backend "azurerm" {
    resource_group_name   = "terraform-storage-rg"
    storage_account_name  = "terraformstate201"
    container_name        = "tfstatefiles"
    key                   = "terraform.tfstate"
  }

Step-04: c3-locals.tf¶

What is ${terraform.workspace}? - It will get the workspace name
Popular Usage-1: Using the workspace name as part of naming or tagging behavior
Popular Usage-2: Referencing the current workspace is useful for changing behavior based on the workspace. For example, for non-default workspaces, it may be useful to spin up smaller cluster sizes.

Replace ${var.environment} with ${terraform.workspace} for all resource names

  rg_name = "${var.business_unit}-${terraform.workspace}-${var.resoure_group_name}"
  vnet_name = "${var.business_unit}-${terraform.workspace}-${var.virtual_network_name}"
  snet_name = "${var.business_unit}-${terraform.workspace}-${var.subnet_name}"
  pip_name = "${var.business_unit}-${terraform.workspace}-${var.publicip_name}"
  nic_name = "${var.business_unit}-${terraform.workspace}-${var.network_interface_name}"
  vm_name = "${var.business_unit}-${terraform.workspace}-${var.virtual_machine_name}"

Step-05: c5-virtual-network.tf¶

Update Public IP domain_name_label with ${terraform.workspace}

# Create Public IP Address
resource "azurerm_public_ip" "mypublicip" {
  name                = local.pip_name
  resource_group_name = azurerm_resource_group.myrg.name
  location            = azurerm_resource_group.myrg.location
  allocation_method   = "Static"
  domain_name_label = "app1-${terraform.workspace}-${random_string.myrandom.id}"
  tags = local.common_tags
}

Step-06: Create resources in default workspaces¶

Default Workspace: Every initialized working directory has at least one workspace.
If you haven't created other workspaces, it is a workspace named default
For a given working directory, only one workspace can be selected at a time.

Most Terraform commands (including provisioning and state manipulation commands) only interact with the currently selected workspace.

# Terraform Init
terraform init 

# List Workspaces
terraform workspace list

# Output Current Workspace using show
terraform workspace show

# Terraform Plan
terraform plan
Observation: 
1. The names of Resources should have "default" in them in place of environment
2. Resource Group Name: it-default-rg
3. Virtual Network: it-default-vnet
4. Subnet Name: it-default-subnet
5. Public IP Name: it-default-publicip
6. Network Interface Name: it-default-nic
7. Virtual Machine Name: it-default-vm

# Terraform Apply
terraform apply -auto-approve

# Verify
Verify the same in Azure Management console
Observation: 
1. The names of Resources should have "default" in them in place of environment
2. Resource Group Name: it-default-rg
3. Virtual Network: it-default-vnet
4. Subnet Name: it-default-subnet
5. Public IP Name: it-default-publicip
6. Network Interface Name: it-default-nic
7. Virtual Machine Name: it-default-vm

# Access Application
http://<public-ip-dns-name>

Step-07: Create New Workspace and Provision Infra¶

# Create New Workspace
terraform workspace new dev

# Verify the folder
cd terraform.tfstate.d 
cd dev
ls
cd ../../

# Terraform Plan
terraform plan
Observation:  
1. The names of Resources should have "dev" in them in place of environment
2. Resource Group Name: it-dev-rg
3. Virtual Network: it-dev-vnet
4. Subnet Name: it-dev-subnet
5. Public IP Name: it-dev-publicip
6. Network Interface Name: it-dev-nic
7. Virtual Machine Name: it-dev-vm

# Terraform Apply
terraform apply -auto-approve

# Verify Dev Workspace statefile
cd terraform.tfstate.d/dev
ls
cd ../../
Observation: You should fine "terraform.tfstate" in "current-working-directory/terraform.tfstate.d/dev" folder

# Verify Resources in Azure mgmt console
Observation:
1. The names of Resources should have "dev" in them in place of environment
2. Resource Group Name: it-dev-rg
3. Virtual Network: it-dev-vnet
4. Subnet Name: it-dev-subnet
5. Public IP Name: it-dev-publicip
6. Network Interface Name: it-dev-nic
7. Virtual Machine Name: it-dev-vm

# Access Application
http://<public-ip-dns-name>

Step-08: Switch workspace and destroy resources¶

Switch workspace from dev to default and destroy resources in default workspace

# Show current workspace
terraform workspace show

# List Worksapces
terraform workspace list

# Workspace select
terraform workspace select default

# Delete Resources from default workspace
terraform destroy -auto-approve

# Verify
1) Verify in Azure Mgmt Console (all the resources should be deleted)

Step-09: Delete dev workspace¶

We cannot delete "default" workspace

We can delete workspaces which we created (dev, qa etc)

# Delete Dev Workspace
terraform workspace delete dev
Observation: Workspace "dev" is not empty.
Deleting "dev" can result in dangling resources: resources that
exist but are no longer manageable by Terraform. Please destroy
these resources first.  If you want to delete this workspace
anyway and risk dangling resources, use the '-force' flag.

# Switch to Dev Workspace
terraform workspace select dev

# Destroy Resources
terraform destroy -auto-approve

# Delete Dev Workspace
terraform workspace delete dev
Observation:
Workspace "dev" is your active workspace.
You cannot delete the currently active workspace. Please switch
to another workspace and try again.

# Switch Workspace to default
terraform workspace select default

# Delete Dev Workspace
terraform workspace delete dev
Observation: Successfully delete workspace dev

# Verify 
In Azure mgmt console, all Resources should be deleted

Step-10: Clean-Up Local folder¶

# Clean-Up local folder
rm -rf .terraform*
rm -rf terraform.tfstate*