vSphere ISO build using JSON without vcenter details

While creating VM with JSON file, the following error came.
1>Vcenter details is not given, but vm is created(not complete)
2>Memory(RAM) is not mapped properly.
3>with normal mode VM is creating and due to bad configuration , it’s destroying. Need a proper template.

ERROR:
vsphere-iso: output will be in this color.

==> vsphere-iso: Creating VM…
==> vsphere-iso: Customizing hardware…
==> vsphere-iso: ServerFaultCode:
==> vsphere-iso: Unexpected element tag “nestedHVEnabled” seen
==> vsphere-iso:
==> vsphere-iso: while parsing serialized DataObject of type vim.vm.ConfigSpec
==> vsphere-iso: at line 2, column 141
==> vsphere-iso:
==> vsphere-iso: while parsing call information for method ReconfigVM_Task
==> vsphere-iso: at line 2, column 66
==> vsphere-iso:
==> vsphere-iso: while parsing SOAP body
==> vsphere-iso: at line 2, column 60
==> vsphere-iso:
==> vsphere-iso: while parsing SOAP envelope
==> vsphere-iso: at line 2, column 0
==> vsphere-iso:
==> vsphere-iso: while parsing HTTP request for method reconfigure
==> vsphere-iso: on object of type vim.VirtualMachine
==> vsphere-iso: at line 1, column 0
==> vsphere-iso: Step “StepConfigureHardware” failed

JSON file details:
{
“builders”: [
{
“type”: “vsphere-iso”,

  "vcenter_server":      "delv3.xxx.com",
  "username":            "root",
  "password":            "iso*help",

  "insecure_connection": "true",

  "vm_name": "absTest3",
  "host": "delv3.xxx.com",

  "guest_os_type": "rhel6_64Guest",

  "ssh_username": "root",
  "ssh_password": "iso*help",
  "datastore": "delv3-datastore3",
  "network": "LR-15.112.155.X",

  "CPUs":             2,
  "RAM":              2048,
  "RAM_reserve_all": true,

  "disk_controller_type":  "pvscsi",
  "disk_size":        16384,

“disk_thin_provisioned”: true,

  "network_card": "vmxnet3",
  "iso_paths": [
    "[delv3-datastore1] RHEL6.8/INTERNAL_USE_LABONLY_UNSUPPORTED_DONOT_DELIVER_BOOT_DVD_JA286-15043.iso"
  ],
  "boot_command": [
    "<enter><wait><enter><wait><HOCOE><wait><enter>",
    "<enter><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs><bs><bs><bs><bs><bs><bs><bs>",
    "<bs><bs><bs>",
    "<enter>"
  ]
}

],

“provisioners”: [
{
“type”: “shell”,
“inline”: [“ls /”]
}
]

}

Have a look at some examples for using the vsphere-iso builder:

Thanks Wolfsrudel for responding my post.

I have followed the ubuntu example, though I am using it for rhel.
As I have mentioned the JSON file in the previous discussion, I found both RAM & CPU has been agreed. For CPU 1 CPU is allotted for for RAM 32 MB.
Do you se any syntax error or should I change anything to achieve it ?