We will be moving some sites from one server to another. What settings should we adjust in the DNS zonefile so that the transition time will be minimized when we switch an account to the new server and update the IP # in the zonefile?

ie, which setting (TTL, Refresh, etc...) and to what value (2 hours, 20 mins., etc...) would be most effective to facilitate a very brief crossover period to minimize problems with dynamic content and e-commerce order systems.

Thanks for any tips!

John C.

Originally posted by JohnCrowley
We will be moving some sites from one server to another. What settings should we adjust in the DNS zonefile so that the transition time will be minimized when we switch an account to the new server and update the IP # in the zonefile?

ie, which setting (TTL, Refresh, etc...) and to what value (2 hours, 20 mins., etc...) would be most effective to facilitate a very brief crossover period to minimize problems with dynamic content and e-commerce order systems.

Thanks for any tips!

John C.

Set the TTL as low as is reasonable and ensure that all slaves have updated.

For example set it to 10 minutes. Then 20 minutes before you make the actual update set it down to 5 seconds. Do the update, and raise the TTL again.

Thanks, that is what I thought (TTL adjustment). Is there a minimum that most nameservers set so they do not refresh any sooner than xx seconds or minutes? Is setting the TTL to 10 seconds going to cause any problems with other nameservers for a short time? If another nameserver has a minimum TTL they accept, and the one I set is less than their threshold, does it default to their minimum value or is it ignored?

Just trying to get a better understanding of how "real" DNS servers will handle this type of switch.

- John C.