{
   "Type" : "AWS::AutoScaling::LaunchConfiguration",
   "Properties" : {
      "ImageId" : "ami-6411e20d",
      "SecurityGroups" : [ { "Ref" : "myEC2SecurityGroup" }, "myExistingEC2SecurityGroup" ],
      "InstanceType" : "m1.small",
      "BlockDeviceMappings" : [ {
            "DeviceName" : "/dev/sdk",
            "Ebs" : {"VolumeSize" : "50"}
         }, {
            "DeviceName" : "/dev/sdc",
            "VirtualName" : "ephemeral0"
      } ]
   }
}