FW: IP Header Checksum 0x0000
"chad scoville" <[email protected]> Thu, 10 Aug 2006 13:56:25 +0000
| Newsgroups | gmane.network.ethereal.user,gmane.spam.detected |
|---|---|
| Message-ID | <W180564321308251155218185@webmail1> |
------------------- The Ethereal project is being continued at a new site. Please go to http://www.wireshark.org and subscribe to [email protected]. Don't forget to unsubscribe from this list at http://www.ethereal.com/mailman/listinfo/ethereal-users ------------------- hi,if all three packets are from the same source, it looks like there is no 3way handshakethe source keeps sending a SYN to the destination - the destination should be replying with a SYN to establish the TCP connection before data transmission can beginI would sniff the cxn to the destination server and see if (1) the syn is received from your source, and (2) if it is, then if a SYN/ACK is sent by the destination back to your source. somewhere along the path between src and dest there are pkts being dropped it appearsagain, unless you have a syn, syn, ack then there is no data transmitted when utilizing TCP as a layer 4 [email protected] wrote on 08/10/2006 09:27:09 AM:> -------------------> The Ethereal project is being continued at a new site. Please go to> http://www.wireshark.org and subscribe to [email protected].> Don't forget to unsubscribe from this list at> http://www.ethereal.com/mailman/listinfo/ethereal-users> -------------------> > > > From: Beasley, Alicia Ms CTR US DISA CDM2 > Sent: Tuesday, August 08, 2006 10:22> To: '[email protected]'> Cc: Robinson, Donald F Mr CTR US DISA CDM3> Subject: IP Header Checksum 0x0000> Ethereal,> I am troubleshooting an issue involving a smtp connection from > our exchange server on one network to an Ironport Mail Relay. The > problem is that email will start building up in the mail queue on > the exchange server and during this time I don't see any packets > traverse between the two devices on the network. An ethereal > capture taken on the exchange server itself shows one difference at > the time right before the mail stops flowing. I have attached three> packets with 0x0000 IP header checksum. > Can someone explain to me what this means? After these three > packets, there are no packets for about 60 seconds and then a new > session starts and mail starts flowing again.> > > Alicia D. Beasley> Systems Analyst II> Central Communications Center (CCC)> DISA Montgomery> > [attachment "exchange-checksum.txt" deleted by Chad Scoville/db/dbcom] > _______________________________________________> Ethereal-users mailing list> [email protected]> http://www.ethereal.com/mailman/listinfo/ethereal-users _______________________________________________ Ethereal-users mailing list [email protected] http://www.ethereal.com/mailman/listinfo/ethereal-users