When creating VMs, it's common to use a username and password to connect to them. While using SSH keys is definitely better for Linux machines, the other day I needed to set a password for an Ubuntu VM

I checked out the Terraform function for creating random strings:

random_password (Resource)

Then I wrote the code below which later re-use in the VM creation module

variable "length" {
  description = "The length input from the user"
  type        = number
  default     = 18
}
resource "random_password" "password" {
  length           = var.length
  special          = true
  override_special = "!#$%&*()-_=+[]{}<>:?"

   keepers = {
    # this will recreate the password if the timestamp changes: meaning every running will generate a new password
    timestamp = "${timestamp()}"
  }
}

output "espassword" {
  value     = random_password.password.result
  sensitive = true
}

/*  Create a random password with the following requirements:
  - Length: 18 default value
  to change the length, use the following command
  export TF_VAR_length=20 in the shell changing the lenght will regenerate the password

   Can also be done using the following command: terraform apply -var 'length=20' -auto-approve
  - Special characters: !#$%&*()-_=+[]{}<>:?
  - Output the password as a sensitive output
  to show the password in the Terraform output
  terraform output espassword
  to regenerate the password
    terraform taint random_password.password
    terraform apply
    terraform output espassword
*/

To execute this code:

1. terraform init

2. terraform plan (optional)

3. terraform apply

4. terraform output espassword. This will show the password string in the console

5. Easier to execute all in 1 liner: terraform apply -auto-approve;terraform output espassword

6. Also, it's possible to create passwords of different length which can be specified at runtime, ex: terraform apply -var 'length=22' -auto-approve;terraform output espassword

Once that done the password will be show in the console, ex:

"w$5(sLht)N>!{IjQ7r" Note: Quotes are not meant to be part of the password

Roberto