nanog mailing list archives
Re: Hotmail blackholing certain IP ranges ?
From: Bruce Campbell <bc-nanog () vicious dropbear id au>
Date: Thu, 26 Apr 2007 09:45:20 +1000 (EST)
On Wed, 25 Apr 2007, Chris Edwards wrote:
Some sites have recently reported problems mailing hotmail due to inability to resolve the hotmail MX records. This appears to be due to the hotmail DNS servers now blackholing DNS queries where the UDP source port was < 1024.
A source port of 53 is permitted through (tested against all listed NSes from multiple locations). TCP queries are dropped, which is a slight worry as the 'any hotmail.com' response is sitting a mere 12 bytes short of the magic 512 byte truncation value.
--==-- Bruce.
Current thread:
- RE: Hotmail blackholing certain IP ranges ?, (continued)
- RE: Hotmail blackholing certain IP ranges ? Gabriel Kuri (Apr 25)
- Re: Hotmail blackholing certain IP ranges ? Richard P. Welty (Apr 25)
- Re: Hotmail blackholing certain IP ranges ? Al Iverson (Apr 25)
- Re: Hotmail blackholing certain IP ranges ? Chris Edwards (Apr 25)
- RE: Hotmail blackholing certain IP ranges ? Leigh Porter (Apr 25)
- Re: Hotmail blackholing certain IP ranges ? Simon Waters (Apr 26)
- Re: Hotmail blackholing certain IP ranges ? Leigh Porter (Apr 26)
- Re: Hotmail blackholing certain IP ranges ? Jeroen Wunnink (Apr 26)
- RE: Hotmail blackholing certain IP ranges ? Stasiniewicz, Adam (Apr 26)
- Re: Hotmail blackholing certain IP ranges ? Al Iverson (Apr 26)
- RE: Hotmail blackholing certain IP ranges ? Leigh Porter (Apr 25)
- Re: Hotmail blackholing certain IP ranges ? Owen DeLong (Apr 26)
- Re: Hotmail blackholing certain IP ranges ? Leigh Porter (Apr 26)