Re: Weird TCP flags?

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On Fri, 2003-12-12 at 09:05, Jeffrey Laramie wrote:
> On Friday 12 December 2003 08:13, Chris Brenton wrote:
> > On Thu, 2003-12-11 at 23:11, Ian Hunter wrote:
> > > Dec 11 22:58:52 lucy kernel: Fwd DMZ->Internet DROP: IN=eth1 OUT=ppp0
> > > SRC=192.168.254.242 DST=204.157.6.223 LEN=60 TOS=0x00 PREC=0x00 TTL=63
> > > ID=56169 DF PROTO=TCP SPT=80 DPT=56319 WINDOW=32476 RES=0x00 ACK SYN
> > > URGP=0
> >
> > My "guess" is, you are receiving a SYN packet from 204.157.6.223. This
> > creates a state table entry with with a 60 second timer. Your system is
> > taking longer than 60 seconds to respond, so iptables is removing the
> > state table entry. Your system then responds causing the log entry shown
> > above.
> >
> 
> Hey Chris,
> 
> Is it normal for the server to send the ACK SYN to a high dport? I wouldn't 
> have expected that.
> 
> Jeff

It will respond to whatever port the user chose we they initiated the
connection.  That should indeed be a high port - John

-- 
John A. Sullivan III
Chief Technology Officer
Nexus Management
+1 207-985-7880
john.sullivan@xxxxxxxxxxxxx
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