<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>Hello,</DIV>
<DIV> </DIV>
<DIV>As I understand it, there are so many PTRs for that IP address, that DNS will change protocol from UDP to TCP.</DIV>
<DIV>
<DIV>So, the message you are getting is informational because of this protocol change.</DIV></DIV>
<DIV>See the long list of PTRs below.</DIV>
<DIV> </DIV>
<DIV>There should be one and only one PTR for that IP.</DIV>
<DIV>Making an SMTP connection to that IP address results in that host saying that it calls itself "minserv.co.za"</DIV>
<DIV>Therefore, there should be only on PTR for that IP address with that hostname.</DIV>
<DIV> </DIV>
<DIV>Note that none of the 15 PTRs match this hostname, which is even more silly.</DIV>
<DIV> </DIV>
<DIV>HTH</DIV>
<DIV> </DIV>
<DIV>$ host 196.7.126.38<BR>;; Truncated, retrying in TCP mode.<BR>38.126.7.196.in-addr.arpa domain name pointer <A href="http://www.adventureservices.co.za">www.adventureservices.co.za</A>.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.penoc.org.za.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.travelsense.net.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.mantlemapper.com.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.quintessentia.net.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.datanetsolutions.co.za.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.spatialdimension.co.za.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.spatialwebserver.co.za.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.spatialwebserver.com.<BR>38.126.7.196.in-addr.arpa domain name pointer mail.adventureservices.co.za.<BR>38.126.7.196.in-addr.arpa domain name pointer
mail.explorationservices.co.za.<BR>38.126.7.196.in-addr.arpa domain name pointer spa004-1.cust-gw.za.mtnbusiness.net.<BR>38.126.7.196.in-addr.arpa domain name pointer <A href="http://www.thewash.co.za">www.thewash.co.za</A>.<BR>38.126.7.196.in-addr.arpa domain name pointer <A href="http://www.gisstaff.co.za">www.gisstaff.co.za</A>.<BR>38.126.7.196.in-addr.arpa domain name pointer <A href="http://www.cheaprentalcars.co.za">www.cheaprentalcars.co.za</A>.<BR></DIV>
<DIV>telnet 196.7.126.38 25<BR>Trying 196.7.126.38...<BR>Connected to 196.7.126.38.<BR>Escape character is '^]'.<BR>220 minserv.co.za Microsoft ESMTP MAIL Service, Version: 6.0.3790.1830 ready at Thu, 9 Jul 2009 14:45:58 +0200<BR>rset<BR>q250 2.0.0 Resetting<BR>uit<BR>221 2.0.0 minserv.co.za Service closing transmission channel<BR>Connection closed by foreign host.<BR></DIV>
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<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Erisan Nyamutenha <Erisan.Nyamutenha@uct.ac.za><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> bind-users-request@lists.isc.org<BR><B><SPAN style="FONT-WEIGHT: bold">Cc:</SPAN></B> bind-users@isc.org<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Thursday, July 9, 2009 3:34:09 AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Truncated, retrying in TCP on Reverse lookup<BR></FONT><BR>
<DIV>Hi All</DIV>
<DIV> </DIV>
<DIV>In order for my email server to accept mail from an external source, it does a reverse lookup on the source. I have email coming from a sender whose ip address maps to several hostnames i.e there PTR records pointing to the same IP. when I try to reverse lookup with my own DNS I get the following ;;Truncated, retrying in TCP mode then eventually I get a time out or server can't find 38.126.7.196.in-addr.arpa: SERVFAIL. What could this be?</DIV>
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