Webmasters Stack Exchange is a question and answer site for pro webmasters. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am attempting to formulate a Disaster Recovery strategy for our company website and would like to know if the following is even possible theoretically or practically?

If I ask our Domain registrar to set our Domain DNS TTL to 3600 permanently, then host our website on a second server that mirrors the primary server will I theoretically be able to switch from primary to secondary in 1 hour limiting our website downtime.

Any advice would be greatly received.

share|improve this question

That should work fine. Operating systems and browsers may cache DNS lookups, so users may see the downtime as longer. (More info here: http://dyn.com/web-browser-dns-caching-bad-thing/).

You could reduce the TTL even further, down to the time it takes your mirror to catch up with changes on your main site.

share|improve this answer
Thank you Paul. – David Clee Feb 1 '12 at 12:15

Most providers won't let you permanently set a low TTL because it significantly increases the load on their servers. Others charge more for a more dynamic service. So it is worth checking that they will do it before you count on it.

share|improve this answer
Hi James,I've checked with ours (123-reg) who seem happy to do this permanently so does that mean you see no other problem with the idea? – David Clee Feb 1 '12 at 14:24

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.