Problem - A large number of dropped segments due to tcp acknowledgement size mismatch (Doc ID 1502762.1)

Last updated on SEPTEMBER 28, 2016

Applies to:

APM - Application Performance Management - Version 11.1.0.0 and later
Information in this document applies to any platform.
***Checked for relevance on 05-May-2014***

Symptoms

When capturing data using RUEI a high number of out-of-sequense packets are seen as well as a high number of dropped segments.
RUEI tool asmon about 60% of the traffic is Future ACK in the TCP screen

All offload functions on the network interface are turned off as per <note 1073610.1> . The data is received from a SPAN port of a network component.

When viewing a tcpdump from the load-balancer and compare the exact same packets on the RUEI host the following is the output of a TCP handshake:

From the Load-balancer:

 
As one can see the SEQ (sequence) in the server response (packet #2) is different in both instances.

Cause

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