<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><DIV>Hi Alan,</DIV>
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<DIV>Thanks for the help.</DIV>
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<DIV>Regards,</DIV>
<DIV>Rock<BR></DIV>
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<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Alan Clegg <aclegg@isc.org><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> bind-users@lists.isc.org<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Fri, July 23, 2010 11:45:08 AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: reject or drop AAAA queries<BR></FONT><BR>On 7/22/2010 8:42 PM, Rock July wrote:<BR>> This is my current setup right now and the reason why I want to reject<BR>> or drop the AAAA queries;<BR>> <BR>> PC Clients: XP, Vista and 7 (Vista and 7 clients are sending both A and<BR>> AAAA queries) send queries to DNS A.<BR>> DNS A: will just forward the query to My DNS<BR>> MyDNS: will query to DNS B in behalf of DNS A.<BR>> DNS B: hosting the domain name (sample: <A href="http://xxx.test.com/" target=_blank>xxx.test.com</A>)<BR>> <BR>> DNS B only hosting A record for xxx.test.com so when it receive AAAA<BR>>
query, it respond "no such name" or NXDOMAIN.<BR>> This result causes negative caching on MyDNS and name resolution will<BR>> also fail for other client computers.<BR>> I only have control on MyDNS so I am thinking if there is any way that I<BR>> can reject/drop those AAAA queries so it will not query to DNS B.<BR><BR>If the server at DNS B is responding with NXDOMAIN to a query for<BR>XXX.TEST.COM AAAA when XXX.TEST.COM A exists, then you need to find<BR>someone else to host <A href="http://test.com/" target=_blank>TEST.COM</A> as DNS B is broken.<BR><BR>AlanC<BR><BR></DIV></DIV></div><br>
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