What is the difference between the _hardRefresh and preferFresh flags?

The difference between _hardRefresh and preferFresh is cache usage. As general rules:

  • If a WHOIS record has an INCOMPLETE_DATA error, it will not be put in cache
  • A WHOIS record is put in cache for 24h (48h for records from whois.godaddy.com)
  • _hardRefresh will force real-time fetch and overwrite the cache yet will cost 5 API credits
  • preferFresh will get you the latest WHOIS record data even if it's incomplete