如何在Vagrant中获取IP地址？

Question

我正在尝试配置一个Hadoop集群，但为此我需要namenode的ip地址。集群本身是由Vagrant创建的，但是直到vagrant在AWS中创建了实例，我才知道ip地址。因此，我有以下Vagrantfile

current_dir = File.dirname(__FILE__)

$master_script = <<SCRIPT
// will write a script to configure 
SCRIPT

Vagrant.configure("2") do |config|
  config.omnibus.chef_version = :latest

  config.vm.provider :aws do |aws, override|
    config.vm.box = "dummy"
    aws.access_key_id = "MY_KEY"
    aws.secret_access_key = "SECRET_KEY"
    aws.keypair_name = "my_key"
    aws.ami = "ami-7747d01e"
    override.ssh.username = "ubuntu"
    override.ssh.private_key_path = "#{current_dir}/my_key.pem"
  end

  config.vm.provider :virtualbox do |v|
      config.vm.box = "precise64"
      config.vm.box_url =  "https://vagrantcloud.com/chef/ubuntu-13.04/version/1/provider/virtualbox.box"
      v.customize ["modifyvm", :id, "--memory", "1024"]
  end

  config.vm.define :namenode do |namenode|
      namenode.vm.box = "dummy"
      namenode.vm.provision :chef_solo do |chef|
         chef.cookbooks_path = "cookbooks"
         chef.roles_path = "roles"
         chef.add_role "cluster"
      end
      namenode.vm.provision :hostmanager
      namenode.vm.provision "shell", :inline => $master_script
  end



config.vm.define :slave do |slave|
      slave.vm.box = "dummy"
      slave.vm.provision :chef_solo do |chef|
         chef.cookbooks_path = "cookbooks"
         chef.roles_path = "roles"
         chef.add_role "cluster"
      end
      slave.vm.provision :hostmanager
      slave.vm.provision "shell", :inline => $master_script
  end
end

我需要用namenode的ip address更新mapred-site.xml and core-site.xml文件。我如何才能获得namenode机器的ip地址，以便更新hadoop配置文件？在食谱中有没有更好的选择，我可以用来完成它？假设我有1个namenode和5个slaves，mapred-site.xml.erb模板将如下所示：

<configuration>
   <property>
      <name>mapred.job.tracker</name>
      <value>hdfs://<%= node[:ipaddress] %>:8021</value>
   </property>
</configuration>

但是，我需要所有namenode和slaves只有namenode的ip地址。我如何在chef中做到这一点？无论哪种方式都适合我，尽管我更喜欢chef解决方案。

Answer 1

您可以：

1-使用namenode实例上的实例元数据服务找出自己的ip：

curl http://169.254.169.254/latest/meta-data/local-ipv4

请参阅：http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AESDG-chapter-instancedata.html

2-标记命名节点(例如: HADOOP_ROLE=NAMENODE)，并在任何实例上使用AWS CLI查找命名节点的本地ip：

aws ec2 describe-instances \
  --region=us-east-1 \
  --filter "Name=tag:HADOOP_ROLE,Values=NAMENODE" \
  --query='Reservations[*].Instances[*].PrivateIpAddress' \
  --output=text

请参阅：http://docs.aws.amazon.com/cli/latest/reference/ec2/describe-instances.html