Installing Terraform

Installing on Mac

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brew tap hashicorp/tap
brew install hashicorp/tap/terraform

Installing on Linux

  1. Ubuntu installation
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curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
sudo apt-get update && sudo apt-get install terraform
  1. CentOS installation
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sudo yum install -y yum-utils
sudo yum-config-manager --add-repo https://rpm.releases.hashicorp.com/RHEL/hashicorp.repo
sudo yum -y install terraform

Verifying Installation

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# terraform -v
Terraform v0.14.3

Your version of Terraform is out of date! The latest version
is 0.14.7. You can update by downloading from https://www.terraform.io/downloads.html
# terraform
Usage: terraform [global options] <subcommand> [args]

The available commands for execution are listed below.
The primary workflow commands are given first, followed by
less common or more advanced commands.

Main commands:
  init          Prepare your working directory for other commands
  validate      Check whether the configuration is valid
  plan          Show changes required by the current configuration
  apply         Create or update infrastructure
  destroy       Destroy previously-created infrastructure

All other commands:
  console       Try Terraform expressions at an interactive command prompt
  fmt           Reformat your configuration in the standard style
  force-unlock  Release a stuck lock on the current workspace
  get           Install or upgrade remote Terraform modules
  graph         Generate a Graphviz graph of the steps in an operation
  import        Associate existing infrastructure with a Terraform resource
  login         Obtain and save credentials for a remote host
  logout        Remove locally-stored credentials for a remote host
  output        Show output values from your root module
  providers     Show the providers required for this configuration
  refresh       Update the state to match remote systems
  show          Show the current state or a saved plan
  state         Advanced state management
  taint         Mark a resource instance as not fully functional
  untaint       Remove the 'tainted' state from a resource instance
  version       Show the current Terraform version
  workspace     Workspace management

Global options (use these before the subcommand, if any):
  -chdir=DIR    Switch to a different working directory before executing the
                given subcommand.
  -help         Show this help output, or the help for a specified subcommand.
  -version      An alias for the "version" subcommand.

Terraform Commands for Resource Management

Initializing Resources

For a Terraform project, I created three basic files: main.tf (entry file), variables.tf (variable definitions), and versions.tf (version information).

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# ls 
main.tf     variables.tf      versions.tf
# terraform init

Initializing the backend...

Initializing provider plugins...
- Reusing previous version of aliyun/alicloud from the dependency lock file
- Using aliyun/alicloud v1.115.1 from the shared cache directory

Terraform has been successfully initialized!

Formatting Terraform Files

fmt automatically reformats .tf files in the current directory to conform to standard Terraform formatting.

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# terraform fmt 
main.tf
variables.tf
versions.tf
# terraform fmt -diff  # Show differences after formatting
main.tf
--- old/main.tf
+++ new/main.tf
@@ -1,7 +1,7 @@
 provider "alicloud" {
   region     = var.region
   access_key = var.alicloud_access_key
-  secret_key =  var.alicloud_secret_key
+  secret_key = var.alicloud_secret_key
 }

 resource "alicloud_vpc" "vpc" {
@@ -12,7 +12,7 @@
 resource "alicloud_vswitch" "vsw" {
   vpc_id            = alicloud_vpc.vpc.id
   cidr_block        = "10.100.0.0/24"
-  availability_zone =  var.availability_zone
+  availability_zone = var.availability_zone
 }

 resource "alicloud_security_group" "default" {
variables.tf
--- old/variables.tf
+++ new/variables.tf
@@ -4,7 +4,7 @@
 }

 variable "alicloud_secret_key" {
-  default                     = "4Z4gbl3d9TGz9jWobv9MPwInvyH2Kf"
+  default     = "4Z4gbl3d9TGz9jWobv9MPwInvyH2Kf"
   description = "The Alicloud Access Secret Key to launch resources.  Support to environment 'ALICLOUD_SECRET_KEY'."
 }

Creating a Resource Plan

terraform plan checks whether the planned changes align with your expectations without modifying actual resources or state.

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# terraform plan

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:

  # alicloud_instance.wanzi_test will be created
  + resource "alicloud_instance" "wanzi_test" {
      + availability_zone             = "cn-hangzhou-i"
      + credit_specification          = (known after apply)
      + deletion_protection           = false
      + dry_run                       = false
      + host_name                     = (known after apply)
      + id                            = (known after apply)
      + image_id                      = "ubuntu_18_04_64_20G_alibase_20190624.vhd"
      + instance_charge_type          = "PostPaid"
      + instance_name                 = "wanzi_tf001"
      + instance_type                 = "ecs.s6-c1m2.small"
      + internet_max_bandwidth_in     = (known after apply)
      + internet_max_bandwidth_out    = 0
      + key_name                      = (known after apply)
      + password                      = (sensitive value)
      + private_ip                    = (known after apply)
      + public_ip                     = (known after apply)
      + role_name                     = (known after apply)
      + security_groups               = (known after apply)
      + spot_strategy                 = "NoSpot"
      + status                        = "Running"
      + subnet_id                     = (known after apply)
      + system_disk_category          = "cloud_efficiency"
      + system_disk_performance_level = (known after apply)
      + system_disk_size              = 40
      + volume_tags                   = (known after apply)
      + vswitch_id                    = (known after apply)
    }

Creating Cloud Resources

terraform apply generates a creation plan and executes it, creating resources and generating a terraform.tfstate file in the current directory.

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# terraform apply
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:

  # alicloud_instance.wanzi_test will be created
  + resource "alicloud_instance" "wanzi_test" {
      + availability_zone             = "cn-hangzhou-i"
      + credit_specification          = (known after apply)
      + deletion_protection           = false
      + dry_run                       = false
      + host_name                     = (known after apply)
      + id                            = (known after apply)
      + image_id                      = "ubuntu_18_04_64_20G_alibase_20190624.vhd"
      + instance_charge_type          = "PostPaid"
      + instance_name                 = "wanzi_tf001"
      + instance_type                 = "ecs.s6-c1m2.small"
      + internet_max_bandwidth_in     = (known after apply)
      + internet_max_bandwidth_out    = 0
      + key_name                      = (known after apply)
      + password                      = (sensitive value)
      + private_ip                    = (known after apply)
      + public_ip                     = (known after apply)
      + role_name                     = (known after apply)
      + security_groups               = (known after apply)
      + spot_strategy                 = "NoSpot"
      + status                        = "Running"
      + subnet_id                     = (known after apply)
      + system_disk_category          = "cloud_efficiency"
      + system_disk_performance_level = (known after apply)
      + system_disk_size              = 40
      + volume_tags                   = (known after apply)
      + vswitch_id                    = (known after apply)
    }

  # alicloud_security_group.default will be created
  + resource "alicloud_security_group" "default" {
      + id                  = (known after apply)
      + inner_access        = (known after apply)
      + inner_access_policy = (known after apply)
      + name                = "default"
      + security_group_type = "normal"
      + vpc_id              = (known after apply)
    }
......
......
Plan: 5 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

alicloud_vpc.vpc: Creating...
alicloud_vpc.vpc: Creation complete after 9s [id=vpc-bp1kulcyygsi727aay4hd]
alicloud_security_group.default: Creating...
alicloud_vswitch.vsw: Creating...
alicloud_security_group.default: Creation complete after 1s [id=sg-bp11s5pka9pxtj6pn4xq]
alicloud_security_group_rule.allow_all_tcp: Creating...
alicloud_security_group_rule.allow_all_tcp: Creation complete after 1s [id=sg-bp11s5pka9pxtj6pn4xq:ingress:tcp:1/65535:intranet:0.0.0.0/0:accept:1]
alicloud_vswitch.vsw: Creation complete after 4s [id=vsw-bp1wgpgz9z8y2lfsl2beo]
alicloud_instance.wanzi_test: Creating...
alicloud_instance.wanzi_test: Still creating... [10s elapsed]
alicloud_instance.wanzi_test: Still creating... [20s elapsed]
alicloud_instance.wanzi_test: Creation complete after 22s [id=i-bp1gt9mb9asadff9r2zr]

Apply complete! Resources: 5 added, 0 changed, 0 destroyed.

Viewing Created Resource Information

terraform show displays the resources created in the current project.

terraform show -json displays data in JSON format.

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# terraform show
# alicloud_instance.wanzi_test:
resource "alicloud_instance" "wanzi_test" {
    availability_zone          = "cn-hangzhou-i"
    deletion_protection        = false
    dry_run                    = false
    host_name                  = "iZbp1gt9mb9asadff9r2zrZ"
    id                         = "i-bp1gt9mb9asadff9r2zr"
    image_id                   = "ubuntu_18_04_64_20G_alibase_20190624.vhd"
    instance_charge_type       = "PostPaid"
    instance_name              = "wanzi_tf001"
    instance_type              = "ecs.s6-c1m2.small"
    internet_charge_type       = "PayByTraffic"
    internet_max_bandwidth_in  = -1
    internet_max_bandwidth_out = 0
    password                   = (sensitive value)
    private_ip                 = "10.100.0.234"
    security_groups            = [
        "sg-bp11s5pka9pxtj6pn4xq",
    ]
    spot_price_limit           = 0
    spot_strategy              = "NoSpot"
    status                     = "Running"
    subnet_id                  = "vsw-bp1wgpgz9z8y2lfsl2beo"
    system_disk_category       = "cloud_efficiency"
    system_disk_size           = 40
    volume_tags                = {}
    vswitch_id                 = "vsw-bp1wgpgz9z8y2lfsl2beo"
}

# alicloud_security_group.default:
resource "alicloud_security_group" "default" {
    id                  = "sg-bp11s5pka9pxtj6pn4xq"
    inner_access        = true
    inner_access_policy = "Accept"
    name                = "default"
    security_group_type = "normal"
    vpc_id              = "vpc-bp1kulcyygsi727aay4hd"
}

# alicloud_security_group_rule.allow_all_tcp:
resource "alicloud_security_group_rule" "allow_all_tcp" {
    cidr_ip           = "0.0.0.0/0"
    id                = "sg-bp11s5pka9pxtj6pn4xq:ingress:tcp:1/65535:intranet:0.0.0.0/0:accept:1"
    ip_protocol       = "tcp"
    nic_type          = "intranet"
    policy            = "accept"
    port_range        = "1/65535"
    priority          = 1
    security_group_id = "sg-bp11s5pka9pxtj6pn4xq"
    type              = "ingress"
}

# alicloud_vpc.vpc:
resource "alicloud_vpc" "vpc" {
    cidr_block        = "10.100.0.0/16"
    id                = "vpc-bp1kulcyygsi727aay4hd"
    name              = "tf_test_foo"
    resource_group_id = "rg-acfm2ogp24u3rcy"
    route_table_id    = "vtb-bp1wy8srerq12rta02r03"
    router_id         = "vrt-bp1apvobefvhshksnnwvm"
    router_table_id   = "vtb-bp1wy8srerq12rta02r03"
}

# alicloud_vswitch.vsw:
resource "alicloud_vswitch" "vsw" {
    availability_zone = "cn-hangzhou-i"
    cidr_block        = "10.100.0.0/24"
    id                = "vsw-bp1wgpgz9z8y2lfsl2beo"
    vpc_id            = "vpc-bp1kulcyygsi727aay4hd"
}

Marking a Resource as Tainted

terraform taint marks a resource as “tainted.” When apply is run again, the tainted resource will be destroyed first and then recreated—effectively performing a delete-and-recreate operation on that specific resource.

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# terraform taint alicloud_instance.wanzi_test
Resource instance alicloud_instance.wanzi_test has been marked as tainted.

Conversely, terraform untaint removes the tainted status, restoring the resource to normal state.

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# terraform untaint alicloud_instance.wanzi_test
Resource instance alicloud_instance.wanzi_test has been successfully untainted.

Destroying Cloud Resources

terraform destroy destroys cloud resources based on the current configuration.

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# terraform destroy

Plan: 0 to add, 0 to change, 5 to destroy.

Do you really want to destroy all resources?
  Terraform will destroy all your managed infrastructure, as shown above.
  There is no undo. Only 'yes' will be accepted to confirm.

  Enter a value: yes

alicloud_security_group_rule.allow_all_tcp: Destroying... [id=sg-bp10tup89oothxz8tny1:ingress:tcp:1/65535:intranet:0.0.0.0/0:accept:1]
alicloud_instance.wanzi_test: Destroying... [id=i-bp10ukz4nlr894mhebgl]
alicloud_security_group_rule.allow_all_tcp: Destruction complete after 0s
alicloud_instance.wanzi_test: Still destroying... [id=i-bp10ukz4nlr894mhebgl, 10s elapsed]
alicloud_instance.wanzi_test: Still destroying... [id=i-bp10ukz4nlr894mhebgl, 20s elapsed]
alicloud_instance.wanzi_test: Destruction complete after 28s
alicloud_security_group.default: Destroying... [id=sg-bp10tup89oothxz8tny1]
alicloud_vswitch.vsw: Destroying... [id=vsw-bp1ap7ccst3fjxnw4pnza]
alicloud_security_group.default: Destruction complete after 9s
alicloud_vswitch.vsw: Still destroying... [id=vsw-bp1ap7ccst3fjxnw4pnza, 10s elapsed]
alicloud_vswitch.vsw: Destruction complete after 20s
alicloud_vpc.vpc: Destroying... [id=vpc-bp1obwt5ded2i0zlbu052]
alicloud_vpc.vpc: Destruction complete after 3s

Destroy complete! Resources: 5 destroyed.

Importing Cloud Data into Local Project

terraform import imports cloud instances into local state using their instance ID. It generates a terraform.tfstate file in the local directory. Before importing existing data, back up both terraform.tfstate and the .terraform directory. After importing, use terraform show to view the resource in Terraform format, copy it, and further process it to obtain the .tf resource file content.

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# cat yunduan.tf
resource "alicloud_instance" "test999" {
  # (resource arguments)
}
#
# terraform import alicloud_instance.test999 i-bp1etiv4002h9q27lb97
alicloud_instance.test999: Importing from ID "i-bp1etiv4002h9q27lb97"...
alicloud_instance.test999: Import prepared!
  Prepared alicloud_instance for import
alicloud_instance.test999: Refreshing state... [id=i-bp1etiv4002h9q27lb97]

Import successful!

The resources that were imported are shown above. These resources are now in
your Terraform state and will henceforth be managed by Terraform.
# cat terraform.tfstate
{
  "version": 4,
  "terraform_version": "0.14.3",
  "serial": 1,
  "lineage": "779fad5e-b076-8cfd-6041-f6eef8c88b8a",
  "outputs": {},
  "resources": [
    {
      "mode": "managed",
      "type": "alicloud_instance",
      "name": "test999",
      "provider": "provider[\"registry.terraform.io/aliyun/alicloud\"]",
      "instances": [
        {
          "schema_version": 0,
          "attributes": {
            "allocate_public_ip": null,
            "auto_release_time": "",
            "auto_renew_period": null,
            "availability_zone": "cn-hangzhou-i",
            "credit_specification": "",
            "data_disks": [],
            "deletion_protection": false,
            "description": "",
            "dry_run": null,
            "force_delete": null,
            "host_name": "iZbp1etiv4002h9q27lb97Z",
            "id": "i-bp1etiv4002h9q27lb97",
            "image_id": "ubuntu_18_04_64_20G_alibase_20190624.vhd",
            "include_data_disks": null,
            "instance_charge_type": "PostPaid",
            "instance_name": "wanzi_tf001",
            "instance_type": "ecs.s6-c1m2.small",
            "internet_charge_type": "PayByTraffic",
            "internet_max_bandwidth_in": -1,
            "internet_max_bandwidth_out": 0,
            "io_optimized": null,
            "is_outdated": null,
            "key_name": "",
            "kms_encrypted_password": null,
            "kms_encryption_context": null,
            "password": "",
            "period": null,
            "period_unit": null,
            "private_ip": "10.100.0.169",
            "public_ip": "",
            "renewal_status": null,
            "resource_group_id": "",
            "role_name": "",
            "security_enhancement_strategy": null,
            "security_groups": [
              "sg-bp14pij6g7sjmn9bz92a"
            ],
            "spot_price_limit": 0,
            "spot_strategy": "NoSpot",
            "status": "Running",
            "subnet_id": "vsw-bp1c966jdtiw1qwh2tng8",
            "system_disk_auto_snapshot_policy_id": "",
            "system_disk_category": "cloud_efficiency",
            "system_disk_description": null,
            "system_disk_name": null,
            "system_disk_performance_level": "",
            "system_disk_size": 40,
            "tags": {},
            "timeouts": {
              "create": null,
              "delete": null,
              "update": null
            },
            "user_data": "",
            "volume_tags": {},
            "vswitch_id": "vsw-bp1c966jdtiw1qwh2tng8"
          },
          "sensitive_attributes": [],
          "private": "eyJlMmJmYjczMC1lY2FhLTExZTYtOGY4OC0zNDM2M2JjN2M0YzAiOnsiY3JlYXRlIjo2MDAwMDAwMDAwMDAsImRlbGV0ZSI6MTIwMDAwMDAwMDAwMCwidXBkYXRlIjo2MDAwMDAwMDAwMDB9LCJzY2hlbWFfdmVyc2lvbiI6IjAifQ=="
        }
      ]
    }
  ]
}
# terraform show
# alicloud_instance.test999:
resource "alicloud_instance" "test999" {
    availability_zone          = "cn-hangzhou-i"
    deletion_protection        = false
    host_name                  = "iZbp1etiv4002h9q27lb97Z"
    id                         = "i-bp1etiv4002h9q27lb97"
    image_id                   = "ubuntu_18_04_64_20G_alibase_20190624.vhd"
    instance_charge_type       = "PostPaid"
    instance_name              = "wanzi_tf001"
    instance_type              = "ecs.s6-c1m2.small"
    internet_charge_type       = "PayByTraffic"
    internet_max_bandwidth_in  = -1
    internet_max_bandwidth_out = 0
    private_ip                 = "10.100.0.169"
    security_groups            = [
        "sg-bp14pij6g7sjmn9bz92a",
    ]
    spot_price_limit           = 0
    spot_strategy              = "NoSpot"
    status                     = "Running"
    subnet_id                  = "vsw-bp1c966jdtiw1qwh2tng8"
    system_disk_category       = "cloud_efficiency"
    system_disk_size           = 40
    tags                       = {}
    volume_tags                = {}
    vswitch_id                 = "vsw-bp1c966jdtiw1qwh2tng8"

    timeouts {}
}

Generating Resource Relationship Diagrams

Each template defines resources with varying degrees of interdependencies. terraform graph generates a visual diagram of these relationships:

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# terraform graph
digraph {
        compound = "true"
        newrank = "true"
        subgraph "root" {
                "[root] alicloud_instance.wanzi_test (expand)" [label = "alicloud_instance.wanzi_test", shape = "box"]
                "[root] alicloud_security_group.default (expand)" [label = "alicloud_security_group.default", shape = "box"]
                "[root] alicloud_security_group_rule.allow_all_tcp (expand)" [label = "alicloud_security_group_rule.allow_all_tcp", shape = "box"]
                "[root] alicloud_vpc.vpc (expand)" [label = "alicloud_vpc.vpc", shape = "box"]
                "[root] alicloud_vswitch.vsw (expand)" [label = "alicloud_vswitch.vsw", shape = "box"]
                "[root] provider[\"registry.terraform.io/aliyun/alicloud\"]" [label = "provider[\"registry.terraform.io/aliyun/alicloud\"]", shape = "diamond"]
                "[root] var.alicloud_access_key" [label = "var.alicloud_access_key", shape = "note"]
                "[root] var.alicloud_secret_key" [label = "var.alicloud_secret_key", shape = "note"]
                "[root] var.availability_zone" [label = "var.availability_zone", shape = "note"]
                "[root] var.disk_category" [label = "var.disk_category", shape = "note"]
                "[root] var.disk_size" [label = "var.disk_size", shape = "note"]
                "[root] var.ecs_password" [label = "var.ecs_password", shape = "note"]
                "[root] var.ecs_type" [label = "var.ecs_type", shape = "note"]
                "[root] var.image_id" [label = "var.image_id", shape = "note"]
                "[root] var.internet_charge_type" [label = "var.internet_charge_type", shape = "note"]
                "[root] var.internet_max_bandwidth_out" [label = "var.internet_max_bandwidth_out", shape = "note"]
                "[root] var.region" [label = "var.region", shape = "note"]
                "[root] alicloud_instance.wanzi_test (expand)" -> "[root] alicloud_security_group.default (expand)"
                "[root] alicloud_instance.wanzi_test (expand)" -> "[root] alicloud_vswitch.vsw (expand)"
                "[root] alicloud_instance.wanzi_test (expand)" -> "[root] var.disk_category"
                "[root] alicloud_instance.wanzi_test (expand)" -> "[root] var.ecs_password"
                "[root] alicloud_instance.wanzi_test (expand)" -> "[root] var.ecs_type"
                "[root] alicloud_instance.wanzi_test (expand)" -> "[root] var.image_id"
                "[root] alicloud_security_group.default (expand)" -> "[root] alicloud_vpc.vpc (expand)"
                "[root] alicloud_security_group_rule.allow_all_tcp (expand)" -> "[root] alicloud_security_group.default (expand)"
                "[root] alicloud_vpc.vpc (expand)" -> "[root] provider[\"registry.terraform.io/aliyun/alicloud\"]"
                "[root] alicloud_vswitch.vsw (expand)" -> "[root] alicloud_vpc.vpc (expand)"
                "[root] alicloud_vswitch.vsw (expand)" -> "[root] var.availability_zone"
                "[root] meta.count-boundary (EachMode fixup)" -> "[root] alicloud_instance.wanzi_test (expand)"
                "[root] meta.count-boundary (EachMode fixup)" -> "[root] alicloud_security_group_rule.allow_all_tcp (expand)"
                "[root] meta.count-boundary (EachMode fixup)" -> "[root] var.disk_size"
                "[root] meta.count-boundary (EachMode fixup)" -> "[root] var.internet_charge_type"
                "[root] meta.count-boundary (EachMode fixup)" -> "[root] var.internet_max_bandwidth_out"
                "[root] provider[\"registry.terraform.io/aliyun/alicloud\"] (close)" -> "[root] alicloud_instance.wanzi_test (expand)"
                "[root] provider[\"registry.terraform.io/aliyun/alicloud\"] (close)" -> "[root] alicloud_security_group_rule.allow_all_tcp (expand)"
                "[root] provider[\"registry.terraform.io/aliyun/alicloud\"]" -> "[root] var.alicloud_access_key"
                "[root] provider[\"registry.terraform.io/aliyun/alicloud\"]" -> "[root] var.alicloud_secret_key"
                "[root] provider[\"registry.terraform.io/aliyun/alicloud\"]" -> "[root] var.region"
                "[root] root" -> "[root] meta.count-boundary (EachMode fixup)"
                "[root] root" -> "[root] provider[\"registry.terraform.io/aliyun/alicloud\"] (close)"
        }
}

This output can also be exported directly as an SVG image using terraform graph | dot -Tsvg > graph.svg (requires prior installation of Graphviz: brew install graphviz).

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terraform graph | dot -Tsvg > ~/Downloads/graph.svg

Viewing graph.svg reveals the full resource relationship diagram:

Terraform Commands for State Management

Listing All Resources in Current State

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# terraform state list
alicloud_instance.wanzi_test
alicloud_security_group.default
alicloud_security_group_rule.allow_all_tcp
alicloud_vpc.vpc
alicloud_vswitch.vsw

Viewing Specific Resource Data

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# terraform state show alicloud_vswitch.vsw
# alicloud_vswitch.vsw:
resource "alicloud_vswitch" "vsw" {
    availability_zone = "cn-hangzhou-i"
    cidr_block        = "10.100.0.0/24"
    id                = "vsw-bp1wgpgz9z8y2lfsl2beo"
    vpc_id            = "vpc-bp1kulcyygsi727aay4hd"
}

Removing a Specific Resource from State

terraform state rm <resource_type>.<resource_name> removes a resource from state but does not delete it from the cloud. The resource can later be re-imported from the cloud.

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# terraform state rm alicloud_security_group.default
Removed alicloud_security_group.default
Successfully removed 1 resource instance(s).
# terraform state list
alicloud_instance.wanzi_test
alicloud_vpc.vpc
alicloud_vswitch.vsw
# terraform import alicloud_security_group.default sg-bp11s5pka9pxtj6pn4xq
alicloud_security_group.default: Importing from ID "sg-bp11s5pka9pxtj6pn4xq"...
alicloud_security_group.default: Import prepared!
  Prepared alicloud_security_group for import
alicloud_security_group.default: Refreshing state... [id=sg-bp11s5pka9pxtj6pn4xq]

Import successful!

The resources that were imported are shown above. These resources are now in
your Terraform state and will henceforth be managed by Terraform.

Refreshing Resource State

terraform refresh updates the local state by fetching the latest data from the cloud via API calls.

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# terraform refresh
alicloud_vpc.vpc: Refreshing state... [id=vpc-bp1kulcyygsi727aay4hd]
alicloud_vswitch.vsw: Refreshing state... [id=vsw-bp1wgpgz9z8y2lfsl2beo]
alicloud_security_group.default: Refreshing state... [id=sg-bp11s5pka9pxtj6pn4xq]
alicloud_instance.wanzi_test: Refreshing state... [id=i-bp1gt9mb9asadff9r2zr]