Difference between revisions of "Terraform Operations"

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==AWS Operations==
==AWS Operations==
{{Internal|Terraform AWS Operations|Terraform AWS Operations}}
{{Internal|Terraform AWS Operations|Terraform AWS Operations}}

Revision as of 02:57, 4 December 2019



terraform version


terraform --help
terraform <command> --help


The initialization operation initializes various local settings that will be used by subsequent commands.

The command also downloads provider binaries and, if any modules are used, the module source. 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.


The -upgrade option will additionally check for any newer versions of existing modules and providers that may be available.

Configuration File Formatting

terraform fmt

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


terraform validate



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]

Apply Options


Skip interactive approval of plan before applying.


terraform show

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

It also shows content of terraform.tfstate state file.


Used to extract the value of an output variable from the state file.

All variables are extracted with:

terraform output

A specific variable is extracted with:

terraform output <output-var-name>





Instances can be imported using their ID:

terraform import aws_instance.web i-00000000000


terraform destroy



Advanced state management.

terraform state

Provider-Specific Operations

AWS Operations

Terraform AWS Operations