Provider configuration

To take advantage of the auto-scaling and dask-distributed computing capabilities, Nebari can be deployed on a handful of the most commonly used cloud providers. Nebari utilizes many of the resources these cloud providers have to offer; however, the Kubernetes engine (or service) is at it's core. Each cloud provider has slightly different ways that Kubernetes is configured but fear not, all of this is handled by Nebari.

The provider section of the configuration file allows you to configure the cloud provider that you are deploying to. Including the region, instance types, and other cloud specific configurations.

Select the provider of your choice:

GCP

Google Cloud has the best support for Nebari and is a great default choice for a production deployment. It allows auto-scaling to zero within the node group. There are no major restrictions.

To see available instance types refer to GCP docs.

note

By default the GKE release channel is set to UNSPECIFIED to prevent the cluster from auto-updating. This has the advantage of ensuring that the Kubernetes version doesn't upgrade and potentially introduce breaking changes. If you'd prefer your cluster's Kubernetes version to update automatically, you can specify a release channel; the options are either stable, regular or rapid.

### Provider configuration ###
google_cloud_platform:
  project: test-test-test
  region: us-central1
  kubernetes_version: "1.24.11-gke.1000"
  release_channel: "UNSPECIFIED"  # default is hidden
  node_groups:
    general:
      instance: n1-standard-4
      min_nodes: 1
      max_nodes: 1
    user:
      instance: n1-standard-2
      min_nodes: 0
      max_nodes: 5
    worker:
      instance: n1-standard-2
      min_nodes: 0
      max_nodes: 5

AWS

Amazon Web Services also has support for auto-scaling to zero within the node group with no restrictions.

Consult AWS instance types for possible options.

### Provider configuration ###
amazon_web_services:
  region: us-west-2
  kubernetes_version: "1.18"
  node_groups:
    general:
      instance: "m5.xlarge"
      min_nodes: 1
      max_nodes: 1
    user:
      instance: "m5.large"
      min_nodes: 1
      max_nodes: 5
    worker:
      instance: "m5.large"
      min_nodes: 1
      max_nodes: 5

Permissions boundary (Optional)

Permissions boundaries in AWS is a powerful feature designed to control the maximum permissions a user or role can have within an AWS Identity and Access Management (IAM) policy. By setting a permissions boundary, administrators can enforce restrictions on the extent of permissions that can be granted, even if policies would otherwise allow broader access.

Nebari supports setting permissions boundary while deploying Nebari to be applied on all the policies created by Nebari. Here is an example of how you would set permissions boundary in nebari-config.yaml.

amazon_web_services:
  # the arn for the permission's boundary policy
  permissions_boundary: arn:aws:iam::01234567890:policy/<permissions-boundary-policy-name>

EKS KMS ARN (Optional)

You can use AWS Key Management Service (KMS) to enhance security by encrypting Kubernetes secrets in Amazon Elastic Kubernetes Service (EKS). This approach adds an extra layer of protection for sensitive information, like passwords, credentials, and TLS keys, by applying user-managed encryption keys to Kubernetes secrets, supporting a defense-in-depth strategy.

Nebari supports setting an existing KMS key while deploying Nebari to implement encryption of secrets created in Nebari's EKS cluster. The KMS key must be a Symmetric key set to encrypt and decrypt data.

warning

Enabling EKS cluster secrets encryption, by setting amazon_web_services.eks_kms_arn, is an irreversible action and re-deploying Nebari to try to remove a previously set eks_kms_arn will fail. On the other hand, if you try to change the KMS key in use for cluster encryption, by re-deploying Nebari after setting a different key ARN, the re-deploy should succeed but the KMS key used for encryption will not actually change in the cluster config and the original key will remain set. The integrity of a faulty deployment can be restored, following a failed re-deploy attempt to remove a previously set KMS key, by simply re-deploying Nebari while ensuring eks_kms_arn is set to the original KMS key ARN.

danger

If the KMS key used for envelope encryption of secrets is ever deleted, then there is no way to recover the EKS cluster.

note

After enabling cluster encryption on your cluster, you must encrypt all existing secrets with the new key by running the following command: kubectl get secrets --all-namespaces -o json | kubectl annotate --overwrite -f - kms-encryption-timestamp="time value" Consult Encrypt K8s secrets with AWS KMS on existing clusters for more information.

Here is an example of how you would set KMS key ARN in nebari-config.yaml.

amazon_web_services:
  # the arn for the AWS Key Management Service key
  eks_kms_arn: "arn:aws:kms:us-west-2:01234567890:key/<aws-kms-key-id>"

Launch Templates (Optional)

Nebari supports configuring launch templates for your node groups, enabling you to customize settings like the AMI ID and pre-bootstrap commands. This is particularly useful if you need to use a custom AMI or perform specific actions before the node joins the cluster.

warning

If you add a launch_template to an existing node group that was previously created without one, AWS will treat this as a change requiring the replacement of the entire node group. This action will trigger a reallocation of resources, effectively destroying the current node group and recreating it. This behavior is due to how AWS handles self-managed node groups versus those using launch templates with custom settings.

tip

To avoid unexpected downtime or data loss, consider creating a new node group with the launch template settings and migrating your workloads accordingly. This approach allows you to implement the new configuration without disrupting your existing resources.

Configuring a Launch Template

To configure a launch template for a node group in your nebari-config.yaml, add the launch_template section under the desired node group:

amazon_web_services:
  region: us-west-2
  kubernetes_version: "1.18"
  node_groups:
    custom-node-group:
      instance: "m5.large"
      min_nodes: 1
      max_nodes: 5
      gpu: false  # Set to true if using GPU instances
      launch_template:
        # Replace with your custom AMI ID
        ami_id: ami-0abcdef1234567890
        # Command to run before the node joins the cluster
        pre_bootstrap_command: |
          #!/bin/bash
          # This script is executed before the node is bootstrapped
          # You can use this script to install additional packages or configure the node
          # For example, to install the `htop` package, you can run:
          # sudo apt-get update
          # sudo apt-get install -y htop"

Parameters:

• ami_id (Optional): The ID of the custom AMI to use for the nodes in this group; this assumes the AMI provided is an EKS-optimized AMI derivative. If specified, the ami_type is automatically set to CUSTOM.
• pre_bootstrap_command (Optional): A command or script to execute on the node before it joins the Kubernetes cluster. This can be used for custom setup or configuration tasks. The format should be a single string in conformation with the shell syntax. This command is injected in the user_data field of the launch template. For more information, see User Data.

If you're using a launch_template with a custom ami_id, there's an issue with updating the scaling.desired_size via Nebari configuration (terraform). To scale up, you must recreate the node group or adjust the scaling settings directly in the AWS Console UI (recommended). We are aware of this inconsistency and plan to address it in a future update.

note

If an ami_id is not provided, AWS will use the default Amazon Linux 2 AMI for the specified instance type. You can find the latest optimized AMI IDs for Amazon EKS in your cluster region by inspecting its respective SSM parameters. For more information, see Retrieve recommended Amazon Linux AMI IDs.

Azure

Microsoft Azure has similar settings for Kubernetes version, region, and instance names - using Azure's available values of course.

Azure also requires a field named storage_account_postfix which will have been generated by nebari init. This allows nebari to create a Storage Account bucket that should be globally unique.

### Provider configuration ###
azure:
  region: Central US
  kubernetes_version: 1.19.11
  node_groups:
    general:
      instance: Standard_D4_v3
      min_nodes: 1
      max_nodes: 1
    user:
      instance: Standard_D2_v2
      min_nodes: 0
      max_nodes: 5
    worker:
      instance: Standard_D2_v2
      min_nodes: 0
      max_nodes: 5
  storage_account_postfix: t65ft6q5

Existing Kubernetes clusters

Originally designed for Nebari deployments on a "local" minikube cluster, this feature has now expanded to allow users to deploy Nebari to any existing kubernetes cluster. The default options for an existing deployment are still set to deploy to a minikube cluster.

Deploying to a local existing kubernetes cluster has different options than the cloud providers. kube_context is an optional key that can be used to deploy to a non-default context. The default node selectors will allow pods to be scheduled anywhere. This can be adjusted to schedule pods on different labeled nodes, allowing for similar functionality to node groups in the cloud.

### Provider configuration ###
existing:
  kube_context: minikube
  node_selectors:
    general:
      key: kubernetes.io/os
      value: linux
    user:
      key: kubernetes.io/os
      value: linux
    worker:
      key: kubernetes.io/os
      value: linux

Local (testing)

Local deployment is intended for Nebari deployments on a "local" cluster created and management by Kind. It is great for experimentation and development.

warning

Currently, local mode is only supported for Linux-based operating systems.

### Provider configuration ###
local:
  kube_context: minikube
  node_selectors:
    general:
      key: kubernetes.io/os
      value: linux
    user:
      key: kubernetes.io/os
      value: linux
    worker:
      key: kubernetes.io/os
      value: linux

note

Many of the cloud providers regularly update their internal Kubernetes versions so if you wish to specify a particular version, please check the following resources. This is completely optional as Nebari will, by default, select the most recent version available for your preferred cloud provider: Google Cloud Platform; Amazon Web Services; Microsoft Azure.