up vote 2 down vote favorite
share [g+] share [fb]

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.

link|improve this question
feedback

2 Answers

up vote 1 down vote

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.

link|improve this answer
Thank you Paul. – David Clee Feb 1 at 12:15
feedback
up vote 0 down vote

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.

link|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 at 14:24
feedback

Your Answer

 
or
required, but never shown
discard

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