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<TITLE>RE: Hotmail blackholing certain IP ranges ?</TITLE>
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<P><FONT SIZE=2>Yeah they and a few others started doing this not too long ago (few months). I thought perhaps something common got upgraded/patched but then I just thought that it was a rather odd configuration change..<BR>
<BR>
It certainly is new. A chap I know (for some reason) set his source port for queries to be port 53 and his DNS queries started to fail.<BR>
<BR>
--<BR>
Leigh<BR>
<BR>
<BR>
-----Original Message-----<BR>
From: owner-nanog@merit.edu on behalf of Chris Edwards<BR>
Sent: Wed 4/25/2007 10:43 PM<BR>
To: nanog@merit.edu<BR>
Subject: Re: Hotmail blackholing certain IP ranges ?<BR>
<BR>
<BR>
Some sites have recently reported problems mailing hotmail due to<BR>
inability to resolve the hotmail MX records. This appears to be due to<BR>
the hotmail DNS servers now blackholing DNS queries where the UDP source<BR>
port was < 1024.<BR>
<BR>
I can reproduce this here and now, but don't know if it's new.<BR>
<BR>
Chris<BR>
<BR>
--<BR>
Chris Edwards, Glasgow University Computing Service<BR>
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