On Tue, May 15, 2012 at 9:20 PM, Ed Greshko <Ed.Greshko@xxxxxxxxxxx> wrote: > On 05/16/2012 10:11 AM, JD wrote: >> I have nscd running. >> /etc/resolv.conf starts out with >> nameserver 127.0.0.1 >> nameserver 192.168.1.254 >> >> >> The 192.168.1.254 is the router, which has been a fast and reliable resolver. >> >> So, to test nscd caching behavior, >> I browse (using FF) over to any website. >> After some time, the address is resolved and the page comes up. >> I kill the tab of the page, and open a new tab and aim the browser >> at same url. Browser again says: looking up whatever....com and takes >> several seconds to resolve it. >> >> I thought that nscd is supposed to cache the translation from the >> first lookup. >> >> Am I to believe that the browser is NOT using /etc/resolv.conf? >> If not, what is it using? >> Or could it be that nscd is useless in this respect? >> > > I've not looked at nscd in a long time....but I never could see the value in it and > never could get it to what I thought was a working or useful configuration for my needs. > > No browser or application uses resolv.conf directly. They make calls to the resolver > libraries which in turn use it. > > IMO, if your router does caching name services there really is no benefit to having > systems do their own caching since the overhead of local requests should be small. > However, it seems that your router may not be caching since it is taking several seconds. > > In cases where the router isn't doing caching, or is doing it poorly, I prefer to > simply run bind on a single server and point all the systems to it for resolution. > > With the current Fedora systems this is easy. All one need to do is install bind and > bind-chroot and enable/start the service. On the "bind" host all you need is > 127.0.0.1 defined as a nameserver. Then, if you use a tool such as "wireshark" you > will see that requests will only go out if the answer is not in the cache or the TTL > has expired. > I understand the libs are what make calls to the resolver. But even the resolver must look at /etc/resolv.conf. If it is empty, NOTHING gets resolved. I was using nscd thinking it is a lightweight caching resolver. But as it turns out it is useless. Time for fedora to bury it :) Re: My router: it does very little if any caching - and has no configuration for it at all. I will try bind. Thanx Ed. JD -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
