July 16th, 2003, 09:45 AM
I want to set up a backup server so when the primary is unavailable, the secondary will automatically receive requests. This secondary server will be off-site with a different IP.
This is possible, right?
July 16th, 2003, 09:58 AM
Yes, it is definately possible.
However, I'd like to tell you that the term backup nameserver is a bit misleading. The way it works is:
Client randomly picks up a name-server from all the listed name-servers.
Primary,Secondary(Master,Slave) are treated with the same priority. So, even if your primary server is available - your secondary server will receive requests.
July 16th, 2003, 10:10 AM
Sorry, I was a bit unclear in my question.
I have a WEB server set up and am trying to find the best way for disaster recovery. But before I configure an offsite server and play w/DNS settings, I wanted to have some guidance.
I don't want load-sharing or anything fancy. I just want to keep the site online in the cheapest way possible.
Thanks for the quick response by the way.
July 16th, 2003, 07:03 PM
One solution would be to publish the A records for your domain with low TTL's (around 1 hour) so that they are only cached for that long.
In the event of a disaster with the first machine, you can change the A record to the IP of the backup machine, and the change will propagate across the internet in an hour's time (in theory - unfortunately there are a lot of broken caches on the internet).
This assumes, of course, that your DNS servers are still available in the event of a disaster. The easyDNS service has four nameservers in three different countries to maximise DNS server availability. They've been up 99% (apart from a DoS attack that took place earlier this year), which is pretty impressive.