Dynamic DNS, also commonly called Dyn DNS or DDNS, is a great technology that helps with auto-updating the name servers. Every time when the IP address (IPv4 or IPv6) changes for some reason, that beneficial service is going to refresh the DNS records – A record and AAAA record.
Domain information groper is the full name of the Dig command that is a simple built-in command used for various DNS probing. One of the main advantages it has it’s that you can use it on most Linux distros and any macOS computer. The Dig command allows you to perform quick checks of your DNS in a very simple way. For instance, you can view a specific DNS record or check a name server. You just have to open the Terminal app on your device. It has a command-line interface (CLI), which shows you all of the needed data in its output.
Time-to-live, or for short just TTL, is a value that limits the amount of time or the number of hops that a data packet is set up for being alive. That could be on a network or in the cache memory. Once that time expires, either the number of hops reaches their limit, the data packets won’t be available anymore.