Linode Terraform Guide for Kubernetes Clusters

In this Linode Terraform guide, we'll walk you through setting up a Kubernetes cluster using Terraform on Linode. To get started, you'll need to create a Linode account and install Terraform on your machine.

First, create a new Linode instance to serve as your Kubernetes master node. This instance will need at least 2GB of RAM to run the Kubernetes control plane.

Next, create a new file called `linode.tf` to define your Linode instance and Kubernetes cluster. This file will contain the Terraform configuration for your infrastructure.

In this file, you'll need to specify the Linode region and datacenter where your instance will be created.

To get started with Linode Terraform, you'll first need to install and configure Terraform on your operating system. Installing Terraform is a relatively straightforward process.

You can download the Terraform binary from the Terraform website and place it in a directory that's included in your system's PATH. This will allow you to run the terraform command from any location on your system. To download the binary, use the command specified in the Terraform documentation.

Once Terraform is installed, you'll need to configure it to use the Linode provider. This involves creating a provider block in your Terraform configuration file and specifying the Linode provider. You'll also need to provide your Linode API key in the provider block, which can be obtained from the Linode Manager.

To set up the Linode provider, you'll need to create a provider block in your Terraform configuration file. This block should include your Linode API key, which can be obtained from the Linode Manager. You can then use the Linode CLI to verify the setup and list the available regions.

Before creating a cluster, it's a good idea to install the Linode CLI. You can find the official documentation on installing the Linode CLI here. Once installed, you can use the Linode CLI to authenticate and verify the setup.

To get started with Linode Terraform, you'll need to install Terraform first. You can download the Terraform binary from the Terraform website and place it in a directory that's included in your system's PATH.

Installing Terraform is a relatively straightforward process that can be done on various operating systems. Once you have the binary, you can install it by placing it in a directory that's included in your system's PATH. This will allow you to run the terraform command from any location on your system.

After installing Terraform, you'll need to configure it to use the Linode provider. This involves creating a provider block in your Terraform configuration file and specifying the Linode provider. You'll also need to provide your Linode API key in the provider block, which can be obtained from the Linode Manager.

To verify the setup, you can list the available regions with the Linode CLI command. Once authenticated, you can return to the terminal to finish the rest of the setup. After completing the installation, typing any command will prompt you for an initial setup.

You'll need to set up the Linode API keys for Terraform, which can be done by creating a provider block in your Terraform configuration file. You'll also need to provide your Linode API key in the provider block, which can be obtained from the Linode Manager.

Provisioning an LKE cluster is a straightforward process. You can use one of four options to create a cluster: the web-based LKE cloud manager, the Linode API, the LKE command-line utility, or infrastructure as code tools like Terraform.

You can also define a file containing all the configuration flags and use it as a blueprint to create the cluster, which is a better option than using the user interface.

To create a cluster, you'll need to specify the type of nodes you want to run, and you can use the Linode CLI and infrastructure as code tools to automate the process.

Here are the four options to provision an LKE cluster:

Note that using the web-based interface is discouraged due to its error-prone nature and lack of scalability.

Provisioning an LKE cluster can be done in four different ways, but using the Linode portal is not the most recommended option due to the numerous configuration options and error-prone process.

You can create a cluster via the Linode API, use the LKE command-line utility, or define the cluster using code with a tool such as Terraform.

Terraform is an open-source Infrastructure as a Code tool that allows you to define a plan of what you want to be executed and let it create the resources on your behalf.

To use Terraform, you'll need to install the binary and generate an access token to authenticate and execute instructions on your behalf.

You can create an access token using the following command and then assign it to an environment variable named $LINODE_TOKEN.

Here are the four options to provision an LKE cluster:

Using Terraform requires defining a file containing all the configuration flags and using it as a blueprint to create the cluster.

You can also use the Linode CLI and infrastructure as code tools to create an LKE cluster.

To create a cluster with Terraform, you'll need to define variables like the type of nodes you wish to run in your cluster.

To apply the changes to your LKE cluster, you'll need to use the "terraform apply" command. This command will create or modify the resources as specified in your Terraform configuration file.

Before running "terraform apply", make sure you've run "terraform plan" to generate an execution plan and confirm the changes are correct.

The "terraform apply" command will prompt for confirmation before applying the changes, so be sure to review the plan carefully before proceeding.

Always keep a backup of your Terraform configuration files and state files to easily roll back to a previous version of your infrastructure in case of any issues.

To configure Terraform, you need to change to the directory where you want to store your Terraform code and create a file named backend.tf.

This file should contain a Terraform block that defines an S3 backend and points it to the Linode object storage endpoint for your chosen region. It's essential to set skip_credentials_validation to true to avoid Terraform reaching out to AWS STS to validate access keys.

You should also specify the bucket name, key, and region in the Terraform block. The key is the path in the bucket to the Terraform state file. Make sure to add the .terraform directory to your .gitignore to prevent the state file from being committed.

To configure Terraform, start by changing to the directory where you want to store your Terraform code and create a file named backend.tf. This file should contain a Terraform block that defines an S3 backend and points it to the Linode object storage endpoint for your chosen region.

The block should include the Linode object storage endpoint, the credentials from the Linode-S3 profile, and the bucket name, key, and region. It's essential to set skip_credentials_validation to true to avoid Terraform reaching out to AWS STS to validate the access keys.

Make sure to add the .terraform directory to your .gitignore to prevent the state file from being accidentally committed. This will help keep your code organized and secure.

Here are the essential steps to configure Terraform:

To configure your Kubernetes cluster, you'll need to modify the workernode.tf file. This involves updating several resource blocks to reflect the changes in your setup.

First, rename the "tls_private_key" resource block from "ssh" to "ssh2". This is a straightforward update that ensures your configuration is accurate.

Next, rename the "local_file" resource block from "private_key" to "private_key2". This change is also simple and helps maintain consistency in your configuration.

You'll also need to update the "linode_instance" resource block from "master" to "worker". This change reflects the shift in your cluster's architecture.

Additionally, amend the command "sudo hostnamectl set-hostname kubernetes-master" to "kubernetes-worker". This update ensures that your node is correctly identified in the cluster.

Finally, add the command "sudo sysctl net.bridge.bridge-nf-call-iptables=1" to enable packet filtering and manipulation for network bridging. This allows nodes to see each other and is required for flannel to communicate effectively.

The linode terraform team has been hard at work, making improvements to the platform.

A nil pointer issue has been fixed in linode_instance_disk when a disk creation event fails.

Changes to API Doc urls have been made to point to the new Techdocs, which will likely improve the user experience.

Documentation for linode_object_storage_bucket data source has been added, making it easier for users to understand and work with this feature.

Here are some of the key improvements and updates:

Repo/Ci Improvements were made to enhance the development process.

The slack payload and workflow job syntax were updated by @ykim-akamai in issue #1668.

Validation for device_name attribute of instance config resource was added by @zliang-akamai in issue #1563. This ensures that only accepted values are used for this attribute.

TestAccResourceInstance_requestQuantity was skipped by @zliang-akamai in issue #1575.

A workflow job was added to verify registry publication after release by @zliang-akamai in issue #1527.

Dependency updates are a crucial part of keeping your infrastructure running smoothly, and Terraform is no exception. The latest update for terraform-provider-linode has been released, with several new features and improvements.

One of the notable updates is the addition of Cloud Firewall to LKE nodes after integration test execution. This feature is now available thanks to the efforts of @ykim-akamai in pull request #1617.

The update also includes a change to skip LDE tests and remove LDE capability in testRegion, also made by @ykim-akamai in pull request #1645.

Here's a list of the updated assets:

The update also includes source code in zip and tar.gz formats, available since 2024-11-19T19:49:38Z.

We've got some exciting updates to share with you. The latest version brings improved support for Terraform, a game-changer for Linode users.

Terraform support has been expanded to include the creation and assignment of additional reserved IPs, a feature that's now available in limited availability. This means you can now use Terraform to manage your Linode resources more efficiently.

The test retry system has been simplified, and a fix has been implemented to prevent hangs when certain retryable tests fail. This should make your development process smoother and less prone to errors.

The VM Placement Changes for Terraform are also worth noting, as they provide more flexibility and control over your Linode resources.

We've made some great improvements to our system. One notable fix was for a nil pointer issue in linode_instance_disk when a disk creation event fails.

This issue was addressed by @zliang-akamai in pull request #1560. The fix should make our system more stable and reliable.

We've also updated our API documentation to point to the new Techdocs. This change was made by @jriddle-linode in pull request #1520.

The new Techdocs should provide better documentation and easier access to information. This should make it easier for users to understand how to use our system.

Here are the specific changes made to the API documentation:

These changes should make it easier for users to find the information they need.