<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=iso-8859-1">
<META content="MSHTML 6.00.6000.16809" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV>Hi!</DIV>
<DIV>please note that the load balancers have the health checking function,
which is using dns server's TCP/53, So If U stop it, load balancer will know the
server down. </DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=makr_inc@yahoo.com href="mailto:makr_inc@yahoo.com">Mark Koehler</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=bind-users@lists.isc.org
href="mailto:bind-users@lists.isc.org">bind-users@lists.isc.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Cc:</B> <A title=bind-workers@lists.isc.org
href="mailto:bind-workers@lists.isc.org">bind-workers@lists.isc.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, April 03, 2009 8:26
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> 53/TCP port unresponsive</DIV>
<DIV><BR></DIV>
<TABLE cellSpacing=0 cellPadding=0 border=0>
<TBODY>
<TR>
<TD vAlign=top>Greetings.<BR><BR>We have 4 masters (rsync'd together)
and a pair of load balancers each of which distributes queries to any of
the 4. On the masters, we run Solaris 10 with BIND 9.5P1.
Recently, one of the 4 stopped using TCP on port 53, but UDP traffic
continued unaffected. What would cause the TCP port to stop?
The port was unresponsive from the backside of the load balancers, and
no DNS TCP packets came from the server either. Is there anything
in BIND which would detect and block a potential DOS attack?<BR><BR>
<ADDRESS>Thanx,<BR>mrak</ADDRESS></TD></TR></TBODY></TABLE>
<P>
<HR>
<P></P>_______________________________________________<BR>bind-workers mailing
list<BR>bind-workers@lists.isc.org<BR>https://lists.isc.org/mailman/listinfo/bind-workers</BLOCKQUOTE></BODY></HTML>