Time-To-Live (TTL)
| A record's time-to-live (TTL) is the amount of time that a DNS record will be cached by DNS Resolvers on the Internet. TTL is specified in seconds. When a DNS Resolver retrieves information on your domain name from our DNS servers, it caches that information for the specified TTL. After the TTL has been cached for that amount of time, it expires, and the DNS resolver once again needs to contact our DNS server to get DNS information on your domain. A TTL of 600 (equal to ten minutes) is sufficient for most sites What TTL should you use? Please continue reading... Sitelutions says: Use a high TTL! Sitelutions encourages our users that do not plan to change their DNS Configurations very often to use a high TTL, such as '86400', which means 86,400 seconds, or one day (24 x 60 * 60). Why is it good to use a high TTL? For one, it reduces load on our servers, reduces our bandwidth costs, and enables us to offer higher quality services to our users. Second of all, it typically improves DNS lookup speed, at least slightly, when users access your sites. Why? Because instead of hitting our server each time, they can often rely on cached DNS records held by the DNS Resolver of their ISP. But what if I use Dynamic DNS, or update my DNS information often? Depending on how much site downtime you believe is bearable, set your TTL accordingly. For example, for most small personal sites, even those using our Dynamic DNS services, a minute or two of downtime isn't so terrible. So, set your TTL for 60 or 120. If your IP address changes very regularly and you cannot live with even one minute of downtime, set your TTL for something more like 10 seconds or 5 seconds. Note that while this will help those who access your site to get the most up-to-date DNS information and minimize downtime, it will also put a great deal more load on our servers. |