Starting an Amazon EC2 Instance - AWS SDK for Ruby

Starting an Amazon EC2 Instance

The following example attempts to start the specified Amazon EC2 instance.

# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. # SPDX - License - Identifier: Apache - 2.0 require 'aws-sdk-ec2' # Attempts to start an Amazon Elastic Compute Cloud (Amazon EC2) instance. # # Prerequisites: # # - The Amazon EC2 instance. # # @param ec2_client [Aws::EC2::Client] An initialized EC2 client. # @param instance_id [String] The ID of the instance. # @return [Boolean] true if the instance was started; otherwise, false. # @example # exit 1 unless instance_started?( # Aws::EC2::Client.new(region: 'us-east-1'), # 'i-123abc' # ) def instance_started?(ec2_client, instance_id) response = ec2_client.describe_instance_status(instance_ids: [instance_id]) if response.instance_statuses.count.positive? state = response.instance_statuses[0].instance_state.name case state when 'pending' puts 'Error starting instance: the instance is pending. Try again later.' return false when 'running' puts 'The instance is already running.' return true when 'terminated' puts 'Error starting instance: ' \ 'the instance is terminated, so you cannot start it.' return false end end ec2_client.start_instances(instance_ids: [instance_id]) ec2_client.wait_until(:instance_running, instance_ids: [instance_id]) puts 'Instance started.' return true rescue StandardError => e puts "Error starting instance: #{e.message}" return false end # Full example call: def run_me instance_id = '' region = '' # Print usage information and then stop. if ARGV[0] == '--help' || ARGV[0] == '-h' puts 'Usage: ruby ec2-ruby-example-start-instance-i-123abc.rb ' \ 'INSTANCE_ID REGION ' puts 'Example: ruby ec2-ruby-example-start-instance-i-123abc.rb ' \ 'i-123abc us-east-1' exit 1 # If no values are specified at the command prompt, use these default values. elsif ARGV.count.zero? instance_id = 'i-123abc' region = 'us-east-1' # Otherwise, use the values as specified at the command prompt. else instance_id = ARGV[0] region = ARGV[1] end ec2_client = Aws::EC2::Client.new(region: region) puts "Attempting to start instance '#{instance_id}' " \ '(this might take a few minutes)...' unless instance_started?(ec2_client, instance_id) puts 'Could not start instance.' end end run_me if $PROGRAM_NAME == __FILE__