Port congestion drops, microbursts or something else

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  • Updated 7 months ago
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Hi

BD X8 chassis, BDXA-10G48X module, sw 15.5.2.9

A port operating as 10G is displaying about 2500-4000 pps constant drop rate with "show port congestion" command.
At the same time "show port util" is displaying 13% peak TX BW.

The cause for such a high drop rate with only 13% peak BW is not immediately obvious.
Do you think microbursts might cause this?

"conf ports XX shared-packet-buffer 100" did not make any difference.
As reported by "sh port XX buffer" there is either 8MB or 2MB max shared buffer (depending on configuration).

If this is a microburst issue the solution would be a 2x10GE LAG.
But if this a SW bug the LAG is useless.

The traffic loading this link is (mostly) multicast.

Thanks
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Mick Mocha

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Posted 1 year ago

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Steven Lin, Employee

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Hi Mick,
Did you try to replace the cable,fiber or SFP to ger rid of the physical issue? And you could identify the microburst congestion with Wireshark by youself from below link.
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Steven Lin, Employee

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Bin, Employee

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Hi,

Kindly add "Port congestion" on hub for your reference
https://community.extremenetworks.com/extreme/topics/port-congestion

Best regards,
Bin