View Source ClusterEC2 (libcluster_ec2 v0.8.2)

ClusterEC2

This is an EC2 clustering strategy for libcluster. It currently supports identifying nodes based on EC2 tags.

The default Tags strategy uses ex_aws to query the EC2 DescribeInstances API endpoint. Access to this API should be granted to the EC2 instance profile. See the ExAws docs for additional configuration options.

config :libcluster,
  topologies: [
    example: [
      strategy: ClusterEC2.Strategy.Tags,
      config: [
        ec2_tagname: "elasticbeanstalk:environment-name"
      ],
    ]
  ]

installation

Installation

The package can be installed by adding libcluster_ec2 to your list of dependencies in mix.exs:

def deps do
  [{:libcluster_ec2, "~> 0.5"}]
end

aws-iam-requirements

AWS IAM Requirements

Instances must have an instance role attached. There are two permissions required:

  • ec2:DescribeInstances - Required to determine tag values of the current running instance. Can be restricted by Resource to the current instance running the application
  • ec2:DescribeTags - Required to identify other instances with the same tags
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
                "ec2:DescribeInstances",
                "ec2:DescribeTags"
            ],
            "Resource": "*"
        }
    ]
}

Link to this section Summary

Functions

Queries the local EC2 instance metadata API to determine the aws resource region of the current instance.

Queries the local EC2 instance metadata API to determine the instance ID of the current instance.

Link to this section Functions

Specs

instance_region() :: binary()

Queries the local EC2 instance metadata API to determine the aws resource region of the current instance.

Specs

local_instance_id() :: binary()

Queries the local EC2 instance metadata API to determine the instance ID of the current instance.