Spirent TestCenter: 5.02- After links are broken/restored, PX3-QSFP28 ports stop receiving frames when "Ignore Link Status" is enabled and speed is 10G

Doc ID: KNI15846

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Symptoms

NOTE:

There is another KB about a similar issue but for a different card (MX3/FX3) - Refer to: KNI15790

Customer wants to keep sending traffic while the DUT ports are down
But the port is getting into bad state after DUT link is down
That is, the port level (Port Traffic and Counters -> Basic Traffic Results -> Total Rx Count (Frames) stops incrementing even though the DUT Tx counters indicating that it is sending frames to the Spirent TestCenter (STC) ports.
After the ports get into this state, two of the ports are connected back-to-back and the ports continue to not receive frames even though they are transmitting them.

Environment

Steps To Reproduce:

Connect two PX3 ports back-to-back in 10G speed
Launch the STC GUI and load the attached configuration file
Relocate the ports as needed.
Run the command sequencer
Typically, within the 10 iterations, the command sequence will break out of the loop due to ARP failing
At that point you can observe: a) via capture, that the ports stopped receiving both data plane and control plane (i.e., ARP) frames; b)if the Generators are restarted, the ports will continue to transmit traffic, but the Rx counters indicate that frames are no longer being received.

Workaround:

Taking the ports offline and bringing them online clears the issue for a little while

Explanation/Resolution

Root Cause

Attachments

Attachment

d-5.02-px3_10G-ignore_linkstatus_repro.tcc

Version 4.0

Publish Date 2020-01-24

Categories
Product : PX3,Spirent TestCenter

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