Re: [Demexp-dev] Re: Issue to open an RPC TCP connection on the Internet

[David MENTRE]

[Gerd, I keep you in copy as you might have suggestion. Let me know if
 you don't want to receive further emails. ]

David MENTRE <address@hidden> writes:

> Yes, good suggestion to check with Ethereal. I should have think of it.

Ok, Ethereal shows that, in case of failure, we receive a TCP RST
(Reset).


* First attempt: Packets 1 and 2: DNS query, the marcos server is
62.23.209.244. Packets 3 and 4: my client attemps to open a connection
(TCP SYN) but there seems to be nobody on the remote end (TCP RST).

No.     Time        Source                Destination           Protocol Info
      1 0.000000    81.48.247.21          80.10.246.130         DNS      
Standard query A marcos.ras.eu.org
      2 0.100426    80.10.246.130         81.48.247.21          DNS      
Standard query response A 62.23.209.244 A 62.23.209.248
      3 0.100903    81.48.247.21          62.23.209.244         TCP      33104 
> 50000 [SYN] Seq=0 Ack=0 Win=5840 Len=0 MSS=1460 TSV=8235911 TSER=0 WS=0
      4 0.176396    62.23.209.244         81.48.247.21          TCP      50000 
> 33104 [RST, ACK] Seq=0 Ack=0 Win=0 Len=0


* Second attempt, 6 seconds later. Same behaviour as the first one.

      5 6.630434    81.48.247.21          80.10.246.130         DNS      
Standard query A marcos.ras.eu.org
      6 6.701354    80.10.246.130         81.48.247.21          DNS      
Standard query response A 62.23.209.244 A 62.23.209.248
      7 6.701955    81.48.247.21          62.23.209.244         TCP      33105 
> 50000 [SYN] Seq=0 Ack=0 Win=5840 Len=0 MSS=1460 TSV=8242513 TSER=0 WS=0
      8 6.781301    62.23.209.244         81.48.247.21          TCP      50000 
> 33105 [RST, ACK] Seq=0 Ack=0 Win=0 Len=0


* Third attempt, 13 seconds after the first time. This time it works,
  packets 11, 12 and 13 open the TCP connection. But why?!? Nothing
  should have changed on the server side.


      9 13.491948   81.48.247.21          80.10.246.130         DNS      
Standard query A marcos.ras.eu.org
     10 13.560181   80.10.246.130         81.48.247.21          DNS      
Standard query response A 62.23.209.248 A 62.23.209.244
     11 13.567873   81.48.247.21          62.23.209.248         TCP      33106 
> 50000 [SYN] Seq=0 Ack=0 Win=5840 Len=0 MSS=1460 TSV=8249380 TSER=0 WS=0
     12 13.645158   62.23.209.248         81.48.247.21          TCP      50000 
> 33106 [SYN, ACK] Seq=0 Ack=1 Win=5792 Len=0 MSS=1460 TSV=618210218 
TSER=8249380 WS=0
     13 13.645203   81.48.247.21          62.23.209.248         TCP      33106 
> 50000 [ACK] Seq=1 Ack=1 Win=5840 Len=0 TSV=8249457 TSER=618210218


Best wishes,
d.
-- 
pub  1024D/A3AD7A2A 2004-10-03 David MENTRE <address@hidden>
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