Re: dnscache memory requirements for large number of server files

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On Tue, Sep 7, 2010 at 11:18 AM, Scott Gifford <[email protected]>wrote:

> On Tue, Sep 7, 2010 at 12:44 PM, Lloyd Standish <[email protected]>wrote:
>
>> Hi Daryl and Jeff,
>> Thanks for the information.  I agree that a linear search would not be a
>> good idea.  Adding some sort of hashed lookup sounds like the way to go
>> here.  I'm not very experienced at C (my experience is primarily in perl and
>> bash) and I have little time.
>
>
> Going a bit off-topic for the list I know, but based on your comments
> Lloyd, you may want to look at the Perl module Net::DNS::Nameserver:
>
> http://search.cpan.org/search?query=Net::DNS::Nameserver&mode=all
>
>
> I have had fantastic luck using it to solve small, strange DNS problems
> like the one you are describing.  You could put an instance of dnscache in
> front of it to handle the caching and get answers without going to the Perl
> code, but really for these sorts of things Perl is pretty fast.
>

I know it's been a while, but for what it's worth the pool.ntp.org DNS
servers are running a server based on Net::DNS::Nameserver.  It's not super
fast, but they - happily - do something like 30 million queries a day.
 Making a proxy of sorts that just sends back a fixed response for something
on the blacklist and otherwise just forwards it to a real resolving server /
cache should be pretty easy.

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On Tue, Sep 7, 2010 at 11:18 AM, Scott Gifford <span dir=3D"ltr">&lt;<a hre=
f=3D"mailto:[email protected]">[email protected]</a>&gt;</s=
pan> wrote:<br><div class=3D"gmail_quote"><blockquote class=3D"gmail_quote"=
 style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class=3D"im">On Tue, Sep 7, 2010 at 12:44 PM, Lloyd Standish <span dir=
=3D"ltr">&lt;<a href=3D"mailto:[email protected]" target=3D"_blank">lloyd=
@crnatural.net</a>&gt;</span> wrote:<br></div><div class=3D"gmail_quote"><d=
iv class=3D"im">
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">

Hi Daryl and Jeff,<br>
Thanks for the information. =A0I agree that a linear search would not be a =
good idea. =A0Adding some sort of hashed lookup sounds like the way to go h=
ere. =A0I&#39;m not very experienced at C (my experience is primarily in pe=
rl and bash) and I have little time.</blockquote>


<div><br></div></div><div>Going a bit off-topic for the list I know, but ba=
sed on your comments Lloyd, you may want to look at the Perl module Net::DN=
S::Nameserver:</div><div><br></div></div><blockquote style=3D"margin:0 0 0 =
40px;border:none;padding:0px">


<div class=3D"gmail_quote"><div><a href=3D"http://search.cpan.org/search?qu=
ery=3DNet::DNS::Nameserver&amp;mode=3Dall" target=3D"_blank">http://search.=
cpan.org/search?query=3DNet::DNS::Nameserver&amp;mode=3Dall</a></div></div>=
</blockquote>
<div class=3D"gmail_quote">

<div><br></div><div>I have had fantastic luck using it to solve small, stra=
nge DNS problems like the one you are describing. =A0You could put an insta=
nce of dnscache in front of it to handle the caching and get answers withou=
t going to the Perl code, but really for these sorts of things Perl is pret=
ty fast.</div>
</div></blockquote><div>=A0</div><div>I know it&#39;s been a while, but for=
 what it&#39;s worth the <a href=3D"http://pool.ntp.org">pool.ntp.org</a> D=
NS servers are running a server based on Net::DNS::Nameserver. =A0It&#39;s =
not super fast, but they - happily - do something like 30 million queries a=
 day. =A0Making a proxy of sorts that just sends back a fixed response for =
something on the blacklist and otherwise just forwards it to a real resolvi=
ng server / cache should be pretty easy.</div>
</div>

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