Create EBS Name tag based on attached EC2 instance name.

tag.rb

#!/usr/bin/env ruby

require 'aws-sdk'

ec2 = Aws::EC2::Resource.new

kv = ec2.instances.each do |i|
  begin
    name = i.tags.find{|t| t["key"] == "Name" }.value
  rescue
    name = i.instance_id
  end

  i.block_device_mappings.each do |b|
    device_name = b.device_name.split("/").last
    vol = Aws::EC2::Volume.new(b.ebs.volume_id)

    vol.create_tags(tags: [{key: "Name", value: "#{name}_#{device_name}"}])
  end
end