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New Member

SG300-20 forwarding out all ports

It looks like it started last Friday, and I haven't made any changes to the switch.  All ports appear to be mirroring or forwarding packets.

Any ideas?

Grap from Cacti for the last 12hrs:



Re: SG300-20 forwarding out all ports

Hi Sean

too many questions unanswered in your problem description..Your question is almost like me asking, why did my vehicle, a 1996 toyota corolla start running slow on friday..

A technician  might need to need to know;

  • firmware version on the switch
  • running configuration  or a show debug
  • maybe simultaneous wireshark captures to validate your description
    • To check the traffic type
    • to see if the traffic is originating from a single traffic source NIC

Is the observed traffic an infusion of multicast or broadcast packets from a bad NIC card, dunno

Why not open a case with the good folk at Small Business Support Center (SBSC) and seek their  advice or a solution to the issues. Normally they look at break/fix issue not network performance, but those tremendous folks try their best to help my customers. So  give them a go.

regards Dave

New Member

SG300-20 forwarding out all ports

Hi Sean,

Did you manage to figure this out? I experience the same thing.




SG300-20 forwarding out all ports

Hi Elvind, judging on the date of this topic, I would venture to say he is running older firmware which had a bug every 50 days it would 'broadcast' all traffic on all ports due to the cam table dropping. This bug was fixed on release.

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