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<p class="MsoNormal"><span lang="EN-US">Hi Bind-Users and Devs,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">We are running servers which have an IP netmask of 255.255.255.255 and on which we had configured BIND to “allow-recursion { localnets; };”. In this setting I would expect that only requests from the localhost allow recursion
as there is no localnet. However, BIND allows recursion globally, here – and we were running open resolvers.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Could this be a bug or is this the wanted behavior?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">To the background of my question: Every Parallels Plesk installation brings a BIND with default config set to “allow-recursion { localnets; };”. I would humbly assume that the above described behavior could be the reason
for at least some open resolvers in the wild.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I’m happy to read your comments,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Rolf <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">In article <Pine.NEB.3.96.1000408121723.56992A-100000 at shell-1.enteract.com>,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Lance Spitzner <lspitz at enteract.com> wrote:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">>I am attempting to limit recursive requests<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">>to my internal network only. However,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">> allow-recursion { localnets; };<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">> Doesn't seem to be doing the trick. What<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">> is the proper way of limiting recursive lookups<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">> to a specific system/network?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">That's the way to do it. What seems to be going wrong?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">-- <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Barry Margolin, barmar at genuity.net<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Genuity, Burlington, MA<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">*** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.<o:p></o:p></span></p>
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