Port congestion drops, microbursts or something else


BD X8 chassis, BDXA-10G48X module, sw

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.


3 replies

Userlevel 4
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.
Userlevel 4
Sorry forgot the link
Userlevel 5

Kindly add "Port congestion" on hub for your reference

Best regards,