使用CloudFormation AWS的UserData和cfn-helper之间的区别

Question

I am starting to use CloudFormation for orchestration/provisioning and I see there are two ways to install packages: 我开始将CloudFormation用于业务流程/资源调配，我发现有两种安装软件包的方法：

First way is with a bash script in userdata section, example: 第一种方法是在userdata部分中使用bash脚本 ，例如：

"UserData": {
          "Fn::Base64": {
            "Fn::Join": [
              "\n",
              [
                "#!/bin/bash",
                "apt-get update",
                "apt-get upgrade -y",
                "apt-get install apache2 -y",
                "echo \"<html><body><h1>Welcome</h1>\" > /var/www/index.html",

Another way is to use cfn-init: 另一种方法是使用cfn-init：

"UserData"       : { "Fn::Base64" : { "Fn::Join" : ["", [
             "yum update -y aws-cfn-bootstrap\n",

             "# Install the files and packages from the metadata\n",
             "/opt/aws/bin/cfn-init -v ",
             "         --stack ", { "Ref" : "AWS::StackName" },
             "         --resource WebServerInstance ",
             "         --configsets Install ",
             "         --region ", { "Ref" : "AWS::Region" }, "\n"
        ]]}}

Is there any reasons to use cfn-init and not bash in UserData ? 有什么理由在UserData中使用cfn-init而不使用bash吗？

Answer 1

Actually it makes no difference if you use bash in UserData or cfn-init. 实际上，如果在UserData或cfn-init中使用bash，则没有任何区别。 But to use cnf-init you need to install the package aws-cfn-bootstrap as you have already done and also need to define 但是要使用cnf-init，您需要像已经完成的那样安装软件包aws-cfn-bootstrap，并且还需要定义

"Resources": {
  "MyInstance": {
    "Type": "AWS::EC2::Instance",
    "Metadata" : {
      "AWS::CloudFormation::Init" : {
        "config" : {
          "packages" : {
            :
          },
          "groups" : {
            :
          },
          "users" : {
            :
          },
          "sources" : {
            :
          },
          "files" : {
            :
          },
          "commands" : {
            :
          },
          "services" : {
            :
          }
        }
      }
    },
    "Properties": {
      :
    }
  }
}

cfn-init is like a clean way to get things done instead of you needing to do yum install in bash of UserData though you will get the same outcome from both the methods. cfn-init就像完成任务的一种干净方法，而不是需要在UserData的bash中进行yum安装，尽管这两种方法都可以得到相同的结果。

使用CloudFormation AWS的UserData和cfn-helper之间的区别

问题描述

1 个解决方案

解决方案1
0 2015-08-26 06:58:58

使用CloudFormation AWS的UserData和cfn-helper之间的区别

问题描述

1 个解决方案

解决方案1 0 2015-08-26 06:58:58

解决方案1
0 2015-08-26 06:58:58