Domino on EKS

Domino 4 can run on a Kubernetes cluster provided by AWS Elastic Kubernetes Service. When running on EKS, the Domino 4 architecture uses AWS resources to fulfill the Domino cluster requirements as follows:

../_images/eks_diagram.png
  • Kubernetes control moves to the EKS control plane with managed Kubernetes masters
  • Domino uses a dedicated Auto Scaling Group (ASG) of EKS workers to host the Domino platform
  • ASGs of EKS workers host elastic compute for Domino executions
  • AWS S3 is used to store user data, backups, and logs
  • AWS EFS is used to store Domino Datasets
  • The kubernetes.io/aws-ebs provisioner is used to create persistent volumes for Domino executions
  • Calico is used as a network plugin to support Kubernetes network policies
  • Domino cannot be installed on EKS Fargate, since Fargate does not support stateful workloads with persistent volumes.
  • Instead of EKS Managed Node groups, Domino recommends creating custom node groups to allow for additional control and customized Amazone Machine Images. Domino recommends eksctl, Terraform, or CloudFormation for setting up custom node groups.

All nodes in such a deployment have private IPs, and internode traffic is routed by internal load balancer. Nodes in the cluster can optionally have egress to the Internet through a NAT gateway.




Setting up an EKS cluster for Domino

This section describes how to configure an Amazon EKS cluster for use with Domino.


VPC networking

If you plan to do VPC peering or set up a site-to-site VPN connection to connect your cluster to other resources like data sources or authentication services, be sure to configure your cluster VPC accordingly to avoid any address space collisions.


Namespaces

No namespace configuration is necessary prior to install. Domino will create three namespaces in the cluster during installation, according to the following specifications:

Namespace Contains
platform Durable Domino application, metadata, platform services required for platform operation
compute Ephemeral Domino execution pods launched by user actions in the application
domino-system Domino installation metadata and secrets

Node pools

The EKS cluster must have at least two ASGs that produce worker nodes with the following specifications and distinct node labels, and it may include an optional GPU pool:

Pool Min-Max Instance Disk Labels
platform 3-3 m5.2xlarge 128G dominodatalab.com/node-pool: platform
default 1-20 m5.2xlarge 400G dominodatalab.com/node-pool: default domino/build-node: true
default-gpu (optional) 0-5 p3.2xlarge 400G dominodatalab.com/node-pool: default-gpu nvidia.com/gpu: true

The platform ASG can run in 1 availability zone or across 3 availability zones. If you want Domino to run with some components deployed as highly available ReplicaSets you must use 3 availability zones. Using 2 zones is not supported, as it results in an even number of nodes in a single failure domain. Note that all compute node pools you use should have corresponding ASGs in any AZ used by other node pools. Setting up an isolated node pool in one zone can cause volume affinity issues.

To run the default and default-gpu pools across multiple availability zones, you will need duplicate ASGs in each zone with the same configuration, including the same labels, to ensure pods are delivered to the zone where the required ephemeral volumes are available.

The easiest way to get suitable drivers onto GPU nodes is to use the EKS-optimized AMI distributed by Amazon as the machine image for the GPU node pool.

Additional ASGs can be added with distinct dominodatalab.com/node-pool labels to make other instance types available for Domino executions. Read Managing the Domino compute grid to learn how these different node types are referenced by label from the Domino application.


Network plugin

Domino relies on Kubernetes network policies to manage secure communication between pods in the cluster. Network policies are implemented by the network plugin, so your cluster use a networking solution which supports NetworkPolicy, such as Calico.

Refer to the AWS documentation on installing Calico for your EKS cluster.


Docker bridge

By default, AWS AMIs do not have bridge networking enabled for Docker containers. Domino requires this for environment builds. Add --enable-docker-bridge true to the user data of the launch configuration used by all Domino ASG nodes.

  1. Create a copy of the launch configuration used by each Domino ASG.
  2. Open the User data field and add --enable-docker-bridge true to the copied launch configuration.
  3. Switch the Domino ASGs to use the new launch configuration.
  4. Drain any existing nodes in the ASG.

Dynamic block storage

The EKS cluster must be equipped with an EBS-backed storage class that Domino will use to provision ephemeral volumes for user execution. Consult the following storage class specification as an example.

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: domino-compute-storage
provisioner: kubernetes.io/aws-ebs
parameters:
  type: gp2
  fsType: ext4

Datasets storage

In order to store Datasets in Domino, an EFS (Elastic File System) must be configured. The EFS file system must be provisioned and configured to allow access from the EKS cluster’s ClusterSharedNodeSecurityGroup via TCP on port 2049. Configure a mount point for each availability zone that Domino compute nodes will run in, and record these mount addresses for use when installing Domino. The EFS must be configured with a security group for the shared nodes in the cluster that was setup when running the Domino EKSCTL tool. Furthermore, when creating the EFS you must:

  1. Select the VPC that was created for your Domino cluster
  2. Create a mount target in the availability zone that you setup the Domino cluster in
  3. Select the Public subnet that was setup during your cluster creation (as opposed to the private one)
  4. When adding a security group, ensure that you are selecting the one that contains ClusterSharedNodeSecurityGroup. It should look something like eksctl-$CLUSTER_NAME-cluster-ClusterSharedNodeSecurityGroup, depending on the name of your cluster used in the cluster.yaml file.

Blob storage

When running in EKS, Domino can use Amazon S3 for durable object storage.

Create the following three S3 buckets:

  • 1 bucket for user data
  • 1 bucket for logs
  • 1 bucket for backups

Configure each bucket to permit read and write access from the EKS cluster. This involves applying an IAM policy to the nodes in the cluster like the following:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:ListBucket",
        "s3:GetBucketLocation",
        "s3:ListBucketMultipartUploads"
      ],
      "Resource": [
        "arn:aws:s3:::$your-logs-bucket-name",
        "arn:aws:s3:::$your-backups-bucket-name",
        "arn:aws:s3:::$your-user-data-bucket-name"
      ]
    },
    {
      "Effect": "Allow",
      "Action": [
        "s3:PutObject",
        "s3:GetObject",
        "s3:DeleteObject",
        "s3:ListMultipartUploadParts",
        "s3:AbortMultipartUpload"
      ],
      "Resource": [
        "arn:aws:s3:::$your-logs-bucket-name/*",
        "arn:aws:s3:::$your-backups-bucket-name/*",
        "arn:aws:s3:::$your-user-data-bucket-name/*"
      ]
    }
  ]
}

Record the names of these buckets for use when installing Domino.


Domain

Domino will need to be configured to serve from a specific FQDN. To serve Domino securely over HTTPS, you will also need an SSL certificate that covers the chosen name. Record the FQDN for use when installing Domino.


Checking your EKS cluster

If you’ve applied the configurations described above to your EKS cluster, it should be able to run the Domino cluster requirements checker without errors. If the checker runs successfully, you are ready for Domino to be installed in the cluster.




Sample cluster configuration

See below for a sample YAML configuration file you can use with eksctl, the official EKS command line tool, to create a Domino-compatible cluster.

Note that after creating a cluster with this configuration, you must still create the EFS and S3 storage systems and configure them for access from the cluster as described above.

# $LOCAL_DIR/cluster.yaml

apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig

metadata:
  name: domino-test-cluster
  region: us-west-2

nodeGroups:
  - name: domino-platform
    instanceType: m5.2xlarge
    minSize: 3
    maxSize: 3
    desiredCapacity: 3
    volumeSize: 128
    availabilityZones: ["us-west-2a"]
    labels:
      "dominodatalab.com/node-pool": "platform"
  - name: domino-default
    instanceType: m5.2xlarge
    minSize: 0
    maxSize: 10
    desiredCapacity: 1
    volumeSize: 400
    availabilityZones: ["us-west-2a"]
    labels:
      "dominodatalab.com/node-pool": "default"
      "domino/build-node": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default"
      "k8s.io/cluster-autoscaler/node-template/label/domino/build-node": "true"
    preBootstrapCommands:
      - "cp /etc/docker/daemon.json /etc/docker/daemon_backup.json"
      - "echo -e '.bridge=\"docker0\" | .\"live-restore\"=false' >  /etc/docker/jq_script"
      - "jq -f /etc/docker/jq_script /etc/docker/daemon_backup.json | tee /etc/docker/daemon.json"
      - "systemctl restart docker"
  - name: domino-gpu
    instanceType: p2.8xlarge
    minSize: 0
    maxSize: 5
    volumeSize: 400
    availabilityZones: ["us-west-2a"]
    ami:
      ami-0ad9a8dc09680cfc2
    labels:
      "dominodatalab.com/node-pool": "default-gpu"
      "nvidia.com/gpu": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default-gpu"

availabilityZones: ["us-west-2a", "us-west-2b", "us-west-2c"]



Sample cluster configuration for multiple AZ

See below for a sample YAML configuration file you can use with eksctl, the official EKS command line tool, to create a Domino-compatible cluster spanning multiple availability zones. Note that in order to avoid issues with execution volume affinity, you must create duplicate groups in each AZ.

# $LOCAL_DIR/cluster.yaml

apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig

metadata:
  name: domino-test-cluster
  region: us-west-2

nodeGroups:
  - name: domino-platform-a
    instanceType: m5.2xlarge
    minSize: 1
    maxSize: 3
    desiredCapacity: 1
    volumeSize: 128
    availabilityZones: ["us-west-2a"]
    labels:
      "dominodatalab.com/node-pool": "platform"
nodeGroups:
  - name: domino-platform-b
    instanceType: m5.2xlarge
    minSize: 1
    maxSize: 3
    desiredCapacity: 1
    volumeSize: 128
    availabilityZones: ["us-west-2b"]
    labels:
      "dominodatalab.com/node-pool": "platform"
nodeGroups:
  - name: domino-platform-c
    instanceType: m5.2xlarge
    minSize: 1
    maxSize: 3
    desiredCapacity: 1
    volumeSize: 128
    availabilityZones: ["us-west-2c"]
    labels:
      "dominodatalab.com/node-pool": "platform"
  - name: domino-default-a
    instanceType: m5.2xlarge
    minSize: 0
    maxSize: 3
    volumeSize: 400
    availabilityZones: ["us-west-2a"]
    labels:
      "dominodatalab.com/node-pool": "default"
      "domino/build-node": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default"
      "k8s.io/cluster-autoscaler/node-template/label/domino/build-node": "true"
    preBootstrapCommands:
      - "cp /etc/docker/daemon.json /etc/docker/daemon_backup.json"
      - "echo -e '.bridge=\"docker0\" | .\"live-restore\"=false' >  /etc/docker/jq_script"
      - "jq -f /etc/docker/jq_script /etc/docker/daemon_backup.json | tee /etc/docker/daemon.json"
      - "systemctl restart docker"
  - name: domino-default-b
    instanceType: m5.2xlarge
    minSize: 0
    maxSize: 3
    volumeSize: 400
    availabilityZones: ["us-west-2b"]
    labels:
      "dominodatalab.com/node-pool": "default"
      "domino/build-node": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default"
      "k8s.io/cluster-autoscaler/node-template/label/domino/build-node": "true"
    preBootstrapCommands:
      - "cp /etc/docker/daemon.json /etc/docker/daemon_backup.json"
      - "echo -e '.bridge=\"docker0\" | .\"live-restore\"=false' >  /etc/docker/jq_script"
      - "jq -f /etc/docker/jq_script /etc/docker/daemon_backup.json | tee /etc/docker/daemon.json"
      - "systemctl restart docker"
  - name: domino-default-c
    instanceType: m5.2xlarge
    minSize: 0
    maxSize: 3
    volumeSize: 400
    availabilityZones: ["us-west-2c"]
    labels:
      "dominodatalab.com/node-pool": "default"
      "domino/build-node": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default"
      "k8s.io/cluster-autoscaler/node-template/label/domino/build-node": "true"
    preBootstrapCommands:
      - "cp /etc/docker/daemon.json /etc/docker/daemon_backup.json"
      - "echo -e '.bridge=\"docker0\" | .\"live-restore\"=false' >  /etc/docker/jq_script"
      - "jq -f /etc/docker/jq_script /etc/docker/daemon_backup.json | tee /etc/docker/daemon.json"
      - "systemctl restart docker"
  - name: domino-gpu-a
    instanceType: p2.8xlarge
    minSize: 0
    maxSize: 2
    volumeSize: 400
    availabilityZones: ["us-west-2a"]
    ami:
      ami-0ad9a8dc09680cfc2
    labels:
      "dominodatalab.com/node-pool": "default-gpu"
      "nvidia.com/gpu": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default-gpu"
  - name: domino-gpu-b
    instanceType: p2.8xlarge
    minSize: 0
    maxSize: 2
    volumeSize: 400
    availabilityZones: ["us-west-2b"]
    ami:
      ami-0ad9a8dc09680cfc2
    labels:
      "dominodatalab.com/node-pool": "default-gpu"
      "nvidia.com/gpu": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default-gpu"
  - name: domino-gpu-c
    instanceType: p2.8xlarge
    minSize: 0
    maxSize: 2
    volumeSize: 400
    availabilityZones: ["us-west-2c"]
    ami:
      ami-0ad9a8dc09680cfc2
    labels:
      "dominodatalab.com/node-pool": "default-gpu"
      "nvidia.com/gpu": "true"
    tags:
      "k8s.io/cluster-autoscaler/node-template/label/dominodatalab.com/node-pool": "default-gpu"

availabilityZones: ["us-west-2a", "us-west-2b", "us-west-2c"]