Bind updating serial number
Recommendation: A good rule of thumb is to make your DDNS TTL half the amount of your DHCP lease.
If the IP address lease is set to 60 (1 minute), set your TTL to 30 (30 seconds).
If you set up dynamic DNS for a domain name, you may be asked to provide a TTL for the records.
There is no single answer to the TTL value you should use for a dynamic DNS record.
It is low enough for changes to take effect quickly, but not so low that the DNS servers get overloaded. While technically there is no maximum DNS TTL setting, values over 7 days will silently be rounded down to 7 days.
Recommendation: For most users, a maximum DNS TTL setting of 86400 (24 hours) is a good choice.
If the IP address is 3600 (1 hour), set your TTL to 1800 (30 minutes).
This will return the DNS information (including TTL values) for the domain name: The value “7728” is the TTL for the record in seconds (7,728 seconds = 2 hours 8 minutes).
DNS caching is an important way to reduce load on the servers, and it is best to keep this traffic low.Please note that even if you change the TTL for your domain name, this does not automatically mean every network across the Internet will honor this value.Many internet service providers (ISPs) ignore TTL settings, and check external DNS records on their own schedule.Dynamic DNS (DDNS) is an excellent way to point domain names to a non-static IP address. You want to point home.to a server on your home network; however, you do not have a static IP address from your ISP.
This means the external IP address for your home server will change periodically.At least 24 hours ahead of time, update your TTL to a shorter value.