Force TTL on a Caching Name Server
Mark_Andrews at isc.org
Thu Sep 7 21:31:32 UTC 2006
> howting at gmail.com wrote:
> > I got it working by adding the following 2 lines to the options block:
> > max-cache-ttl 300;
> > max-ncache-ttl 300;
> > After restarting named, dig shows that all TTL are capped at 300 :)
> > This is the perfect solution I wanted. Thanks for all the help!
> Hmm... OK. So if one of your users really likes Hemis (TM) and hits
> http://whatcanyouhemi.com frequently during the course of a day, you
> think it's "perfect" for your nameserver to be querying mine 12 times as
> often as it should be expected to (the TTL I've set on the RRset is 1
> hour, but you're capping it at 5 minutes)? That's an interesting
> definition of "perfect". It's certainly not "perfect" from the
> perspective of my traffic load, my capacity planning for the future, my
> budget, etc.
> The DNS infrastructure of the Internet is held together in large part
> through mutual consent and co-operation. Practices such as you are
> describing undermine those, inasmuch as you are putting a burden on
> others for your own selfish reasons. I would seriously urge you to
> - Kevin
And any competent C programer should be able to add the two
or so lines it would take to cap the ttl in responses w/o
having to effectively kill the cache.
ISC Training! October 16-20, 2006, in the San Francisco Bay Area,
covering topics from DNS to DHCP. Email training at isc.org.
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: Mark_Andrews at isc.org
More information about the bind-users