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I'm facing a strange issue. We have two systems communicating via RFC, but this communication breaks everytime with the following issue:

The Client receives an TCP ACK with an SLE=2734286 and SLR=2777173 Client then starts a retransmission of the "missing" packages Then receives a TCP DUP ACK with SACK: 2777089-2777173 2734286-2777173

This is weird, isnt it? The SACK parameters are overlapping. The Client then sends again the missing packages but always receives the TCP DUP ACK. After 5 tries the client gives up.

Its Windows 2003 to Linux 2.6.32.

Is someone of you aware of such an issue? The Network connection itself is working without issues (for ex. when copying data via SSH, there the SACK protocol seems to work correct).

Thanks and kind regards Stefan

asked 07 Nov '12, 07:13

sLy's gravatar image

accept rate: 0%

you need to supply the ACK number from the Acknowledgements in order to solve this, please provide ACK and SACK information for those packets plus if possible the tcp.len of the data packets

(07 Nov '12, 07:57) Landi

Better yet, put the offending capture on cloudshark for us all to see.

(08 Nov '12, 07:10) Jaap ♦
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question asked: 07 Nov '12, 07:13

question was seen: 2,643 times

last updated: 08 Nov '12, 07:10

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