{
 "if": {
  "not": {
   "required": [
    "Ebs"
   ]
  },
  "required": [
   "VirtualName"
  ]
 },
 "then": {
  "properties": {
   "VirtualName": {
    "pattern": "^ephemeral([0-9]|[1][0-9]|[2][0-3])$"
   }
  }
 }
}
