On Thursday 05 January 2006 13:15, John Hinton wrote:
> It is important to use TTLs for the various services within a specified
> range. Too short will get you ignored, at least after a while. Too
> long.. same thing. I've never had a problem with setting the TTLs low
> for a few days before a transfer or some such, but then set them back up
> into acceptable ranges after the move.
>
> Good help on the proper ranges can be found on http://dnsreport.com
Tried that. Suggestions?
http://dnsreport.com/tools/dnsreport.ch?domain=schoolpathways.com
> Five minutes will more than likely get you ignored after a few days or
> weeks. Imagine if everyone set their TTL to five minutes.. the root
> nameservers would be looking up every record on the net once every five
> minutes... a pretty arduous task for 13 servers. And if you want to find
> out what happens if you don't use cached DNS, try turning it off at the
> router level sometime for fun.... s--------l----------o----------w!!!!
> Heck, 1200bps dialups act like T-1s compared to no caching.
That's fine - but how do I minimize downtime in a failover scenario? (Thus, my
questions about BGP, which you don't seem to mention)
In the past, when I 'cut down' the TTL to 5 minutes, I did so about 1 week
before the switch. (that was the TTL on the domains, so it was the shortest I
could do it.) I still had the aforementioned problem.
-Ben
--
"The best way to predict the future is to invent it."
- XEROX PARC slogan, circa 1978
