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AWS

To deploy kubespray on AWS uncomment the cloud_provider option in group_vars/all.yml and set it to 'aws'. Refer to the Kubespray Configuration for customizing the provider.

Prior to creating your instances, you must ensure that you have created IAM roles and policies for both "kubernetes-master" and "kubernetes-node". You can find the IAM policies here. See the IAM Documentation if guidance is needed on how to set these up. When you bring your instances online, associate them with the respective IAM role. Nodes that are only to be used for Etcd do not need a role.

You would also need to tag the resources in your VPC accordingly for the aws provider to utilize them. Tag the subnets, route tables and all instances that kubernetes will be run on with key kubernetes.io/cluster/$cluster_name ($cluster_name must be a unique identifier for the cluster). Tag the subnets that must be targetted by external ELBs with the key kubernetes.io/role/elb and internal ELBs with the key kubernetes.io/role/internal-elb.

Make sure your VPC has both DNS Hostnames support and Private DNS enabled.

The next step is to make sure the hostnames in your inventory file are identical to your internal hostnames in AWS. This may look something like ip-111-222-333-444.us-west-2.compute.internal. You can then specify how Ansible connects to these instances with ansible_ssh_host and ansible_ssh_user.

You can now create your cluster!

Dynamic Inventory

There is also a dynamic inventory script for AWS that can be used if desired. However, be aware that it makes some certain assumptions about how you'll create your inventory. It also does not handle all use cases and groups that we may use as part of more advanced deployments. Additions welcome.

This will produce an inventory that is passed into Ansible that looks like the following:

{
  "_meta": {
    "hostvars": {
      "ip-172-31-3-xxx.us-east-2.compute.internal": {
        "ansible_ssh_host": "172.31.3.xxx"
      },
      "ip-172-31-8-xxx.us-east-2.compute.internal": {
        "ansible_ssh_host": "172.31.8.xxx"
      }
    }
  },
  "etcd": [
    "ip-172-31-3-xxx.us-east-2.compute.internal"
  ],
  "k8s-cluster": {
    "children": [
      "kube-master",
      "kube-node"
    ]
  },
  "kube-master": [
    "ip-172-31-3-xxx.us-east-2.compute.internal"
  ],
  "kube-node": [
    "ip-172-31-8-xxx.us-east-2.compute.internal"
  ]
}

Guide:

  • Create instances in AWS as needed.
  • Either during or after creation, add tags to the instances with a key of kubespray-role and a value of kube-master, etcd, or kube-node. You can also share roles like kube-master, etcd
  • Copy the kubespray-aws-inventory.py script from kubespray/contrib/aws_inventory to the kubespray/inventory directory.
  • Set the following AWS credentials and info as environment variables in your terminal:
export AWS_ACCESS_KEY_ID="xxxxx"
export AWS_SECRET_ACCESS_KEY="yyyyy"
export REGION="us-east-2"
  • We will now create our cluster. There will be either one or two small changes. The first is that we will specify -i inventory/kubespray-aws-inventory.py as our inventory script. The other is conditional. If your AWS instances are public facing, you can set the VPC_VISIBILITY variable to public and that will result in public IP and DNS names being passed into the inventory. This causes your cluster.yml command to look like VPC_VISIBILITY="public" ansible-playbook ... cluster.yml

Kubespray configuration

Declare the cloud config variables for the aws provider as follows. Setting these variables are optional and depend on your use case.

Variable Type Comment
aws_zone string Force set the AWS zone. Recommended to leave blank.
aws_vpc string The AWS VPC flag enables the possibility to run the master components on a different aws account, on a different cloud provider or on-premise. If the flag is set also the KubernetesClusterTag must be provided
aws_subnet_id string SubnetID enables using a specific subnet to use for ELB's
aws_route_table_id string RouteTableID enables using a specific RouteTable
aws_role_arn string RoleARN is the IAM role to assume when interaction with AWS APIs
aws_kubernetes_cluster_tag string KubernetesClusterTag is the legacy cluster id we'll use to identify our cluster resources
aws_kubernetes_cluster_id string KubernetesClusterID is the cluster id we'll use to identify our cluster resources
aws_disable_security_group_ingress bool The aws provider creates an inbound rule per load balancer on the node security group. However, this can run into the AWS security group rule limit of 50 if many LoadBalancers are created. This flag disables the automatic ingress creation. It requires that the user has setup a rule that allows inbound traffic on kubelet ports from the local VPC subnet (so load balancers can access it). E.g. 10.82.0.0/16 30000-32000.
aws_elb_security_group string Only in Kubelet version >= 1.7 : AWS has a hard limit of 500 security groups. For large clusters creating a security group for each ELB can cause the max number of security groups to be reached. If this is set instead of creating a new Security group for each ELB this security group will be used instead.
aws_disable_strict_zone_check bool During the instantiation of an new AWS cloud provider, the detected region is validated against a known set of regions. In a non-standard, AWS like environment (e.g. Eucalyptus), this check may be undesirable. Setting this to true will disable the check and provide a warning that the check was skipped. Please note that this is an experimental feature and work-in-progress for the moment.