Terraform Operations

Internal

• Terraform

Version

terraform version

Help

terraform --help
terraform <command> --help

Initialization

The initialization operation initializes various local settings that will be used by subsequent commands. The command also downloads provider binaries. The command needs to be re-run if new modules are set or changed, or backend configuration changes.

terraform init

The command creates a .terraform directory, which contains a "plugins" sub-directory.

Configuration File Formatting

terraform fmt

Formats all .tf in the current directory. It aligns equals, etc. Formatting enables standardization.

Apply

https://www.terraform.io/docs/commands/apply.html

terraform apply

The output shows the execution plan, in a format similar to diff.

-/+ means the resource will be destroyed and recreated rather than update it in-place. ~ means update in-place.

An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # aws_instance.terraform-test-01 will be created
  + resource "aws_instance" "terraform-test-01" {
      + ami                          = "ami-a6faba49dddaecfb7"
      + arn                          = (known after apply)
      + associate_public_ip_address  = (known after apply)
      + availability_zone            = (known after apply)
      + cpu_core_count               = (known after apply)
      + cpu_threads_per_core         = (known after apply)
      + get_password_data            = false
      + host_id                      = (known after apply)
      + id                           = (known after apply)
      + instance_state               = (known after apply)
      + instance_type                = "m5.4xlarge"
      + ipv6_address_count           = (known after apply)
      + ipv6_addresses               = (known after apply)
      + key_name                     = (known after apply)
      + network_interface_id         = (known after apply)
      + password_data                = (known after apply)
      + placement_group              = (known after apply)
      + primary_network_interface_id = (known after apply)
      + private_dns                  = (known after apply)
      + private_ip                   = (known after apply)
      + public_dns                   = (known after apply)
      + public_ip                    = (known after apply)
      + security_groups              = (known after apply)
      + source_dest_check            = true
      + subnet_id                    = (known after apply)
      + tenancy                      = (known after apply)
      + volume_tags                  = (known after apply)
      + vpc_security_group_ids       = (known after apply)

      + ebs_block_device {
          + delete_on_termination = (known after apply)
          + device_name           = (known after apply)
          + encrypted             = (known after apply)
          + iops                  = (known after apply)
          + kms_key_id            = (known after apply)
          + snapshot_id           = (known after apply)
          + volume_id             = (known after apply)
          + volume_size           = (known after apply)
          + volume_type           = (known after apply)
        }

      + ephemeral_block_device {
          + device_name  = (known after apply)
          + no_device    = (known after apply)
          + virtual_name = (known after apply)
        }

      + network_interface {
          + delete_on_termination = (known after apply)
          + device_index          = (known after apply)
          + network_interface_id  = (known after apply)
        }

      + root_block_device {
          + delete_on_termination = (known after apply)
          + encrypted             = (known after apply)
          + iops                  = (known after apply)
          + kms_key_id            = (known after apply)
          + volume_id             = (known after apply)
          + volume_size           = (known after apply)
          + volume_type           = (known after apply)
        }
    }

Plan: 1 to add, 0 to change, 0 to destroy.

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

aws_instance.terraform-test-01: Creating...
aws_instance.terraform-test-01: Still creating... [10s elapsed]
aws_instance.terraform-test-01: Still creating... [20s elapsed]
aws_instance.terraform-test-01: Creation complete after 24s [id=i-afbbc2c4a789ab871]

Show

terraform show

Shows the state. It contain interesting information obtained after installation, such as IP addresses, etc.

Import

Instances can be imported using their ID:

terraform import aws_instance.web i-00000000000

Destroy

https://learn.hashicorp.com/terraform/getting-started/destroy#destroy

terraform destroy

Provider-Specific Operations

AWS Operations

Terraform AWS Operations