[sf-lug] multiple dns lookups for one page?

[Nathan Hoover]

Interestingly, I am seeing the same behavior on my machine. My first
inclination was that Firebug was erroneously reporting DNS lookup time, but
I discounted that quickly by looking at one of my own sites, and not
observing a similar pattern. My next inclination was that it was a DNS
configuration problem (ridiculously low TTL?) but a quick look doesn't seem
to bear that out either. Now my curiosity is piqued! If I find anything,
I'll let everyone know.

Nathan

On Thu, Apr 15, 2010 at 11:18 AM, Rick Moen <rick at linuxmafia.com> wrote:

> Quoting Andrew E (andrewevansc at gmail.com):
>
> > CONFIDENTIAL:
>
> [RM: snip server URL and related text, which I'm pretty sure were the
> only confidential parts]
>
> > Firebug shows me a whole bunch of DNS lookups. Does it look like that
> IPv6
> > vs IPv4 issue? I'm unfamiliar with how to diagnose issues with these
> > protocols or DNS in general. Here is a phpinfo() about the server
> > http://native-instinct.com/portfolio/info.php if that helps.
>
> As Nathan said, and I was implying, Firebug is reporting what's going on
> at the machine where _Firebug_ is running, which is where your Web
> browser is -- which Web browser I believe would be Firefox, right?
>
> So, the real question you should be asking yourself is, where's your
> Web-browsing machine (the machine you're running your -browser- on)
> consulting for DNS?  Is the Web-browsing machine attempting IPv6-enabled
> DNS and falling back to IPv4-based queries when those fail?
>
> One quick way to check is to install Unbound, an IP6-enabled open-source
> recursive nameserver available for Unixes (including Linux and OS X) and
> MS-Windows, pointing your machine at it for nameservice, and seeing if
> the problem goes away.
>
> The URL I posted earlier details how.
>
>
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