packer issue

vagrant-centos-local.json

{
  "variables": {
    "iso_url": "",
    "iso_checksum": "",
    "iso_checksum_type": "sha256",
    "redhat_release": "",
    "redhat_platform": "x86_64",
    "artifact_description": "",
    "artifact_version": "",
    "ssh_username": "vagrant",
    "ssh_password": "vagrant",
    "disk_size": "20480",
  "iso_url": "http://ftp.byfly.by/pub/CentOS/7/isos/x86_64/CentOS-7-x86_64-Minimal-1708.iso",
  "iso_checksum": "bba314624956961a2ea31dd460cd860a77911c1e0a56e4820a12b9c5dad363f5",
  "artifact_description": "CentOS 7.4 (build 1708): CentOS-7-x86_64-Minimal-1708.iso, 20GB /, nothing extra",
  "artifact_version": "7.4.1708",
  "redhat_release": "7.4",
    "output_path": "D:/Temp/packer"
  },

  "builders": [
    {   
      "name": "centos-{{user `redhat_release`}}",
      "type": "virtualbox-iso",
      "vm_name": "packer-centos-vm",

      "boot_wait": "10s",
      "disk_size": "{{user `disk_size`}}",
      "guest_os_type": "RedHat_64",
      "http_directory": "http",
      "output_directory": "{{user `output_path`}}/output",

      "iso_url": "{{user `iso_url`}}",
      "iso_checksum": "{{user `iso_checksum`}}",
      "iso_checksum_type": "{{user `iso_checksum_type`}}",
      "guest_additions_path": "{{user `output_path`}}/VBoxGuestAdditions.iso",

      "boot_command": [
        "<tab> text ks=http://{{ .HTTPIP }}:{{ .HTTPPort }}/vagrant.ks<enter><wait>"
      ],

      "shutdown_command": "sudo -S /sbin/halt -h -p",
      "shutdown_timeout" : "5m",
      
      "ssh_wait_timeout": "15m",
      "ssh_username": "{{user `ssh_username`}}",
      "ssh_password": "{{user `ssh_password`}}",
      "ssh_port": 22,
      "ssh_pty": true,

      "vboxmanage": [
        [  "modifyvm",  "{{.Name}}",  "--memory",  "1024" ],
        [  "modifyvm",  "{{.Name}}",  "--cpus",  "2" ]
      ],
      "hard_drive_interface": "sata",
      "virtualbox_version_file": ".vbox_version",

      "export_opts":
      [
        "--manifest",
        "--vsys", "0",
        "--description", "{{user `artifact_description`}}",
        "--version", "{{user `artifact_version`}}"
      ]

    }
  ], 
  
  "post-processors": [
    {
      "output": "{{user `output_path`}}/sbeliakou-vagrant-centos-{{user `redhat_release`}}-{{user `redhat_platform`}}-minimal.box",
      "compression_level": "6",
      "type": "vagrant"
    }
  ],
  
  "provisioners": [
    {
      "type": "shell",
      "execute_command": "{{.Vars}} sudo -S -E bash '{{.Path}}'",
      "start_retry_timeout": "1m",
      "expect_disconnect": true,
      "pause_before": "5s",
      "override": {
        "centos-{{user `redhat_release`}}": {
          "scripts": [
            "scripts/base.sh",
            "scripts/vagrant.sh",
            "scripts/virtualbox.sh",
            "scripts/cleanup.sh"
          ]
        }
      }
    }
  ]
}