SystemHostname (type)

{
  "id": "SystemHostname", 
  "maxLength": 255, 
  "pattern": "^(?=.{1,255}$)[0-9A-Za-z](?:(?:[0-9A-Za-z]|-){0,61}[0-9A-Za-z])?(?:\\.[0-9A-Za-z](?:(?:[0-9A-Za-z]|-){0,61}[0-9A-Za-z])?)*\\.?$", 
  "title": "System host name", 
  "type": "string"
}