I learned that IP address can be hidden by using cloudflare, and the importance of updating old record. Old record can be used to brute force and hack the new website that have been updated by using specific website to gather information, such as dnstrails.com. we can get the historical data of the website and get the old script that may contain vulnerable code of their old website like database, etc.
IP address
mail server that is used by google
DNS server
