Default Domain TTL
The Time to Live (TTL) of a domain name tells other DNS servers how long to hold onto a DNS record after it has been queried. The default TTL is set to 1 hour. This means when someone looks up your website for example, they receive the IP address of where your website is hosted from our DNS servers. Our DNS servers then specify how long the requesting DNS server should cache that record (1 hour) before requesting the record again.
Under the Zone Management interface, you can modify the TTL for your domain name down to 5 minutes. So this will mean that any records requested will have a maximum cache time of 5 minutes.
Examples of Use
Lowering the TTL before making a record change will lower the update time for the new record. This is ideal for times that you are transferring web hosting providers, mail hosts, or changing your office static IP address and wish to minimise any downtime while the new record propagates. Lower the TTL first, then wait a few hours for the previous TTL cache to expire before changing your record. Once you're all switched over, reset the TTL back to a more reasonable time such as 1 or 3 hours.
You might choose to use the 5 minute TTL permanently if you have a backup web host or fail-over site available. So in the event that your usual host is unavailable, you can login and quickly update the DNS record to point to your backup host and the maximum time before this becomes live will be only 5 minutes.
