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Guide

Feb 15, 2017

Solved

STP Leak using Broadcast packet 01:80:c2:00:00:1c

Netgear Support, Please take note that the community and several customers have discovered a possible flaw in your STP implementation that causes CPU panic and circular broadcasts that disable sw...

Firmware

Hardware

Security

DaneA
Jun 07, 2017
LarryV and to others,

Since a firmware fix is not yet available, the MAC ACL workaround can be used as described on the article below:

Adding a MAC ACL on Fully and Smart Managed switches to prevent STP leak of multicast packet from 3rd party access points

Regards,

DaneA

NETGEAR Communtiy Team

Retired_Member

Mar 13, 2017

Hi RedTechie and elderone,

We didn't reproduce the issue locally with 1* M7100 (v11.0.0.28) and 2* GS728TXS (v6.1.0.35), 2 GS728TXS are in stacking, and connect to M7100 through LACP, enable RSTP on all ports and LAGs.

Then use two IXIA ports to simulate broadcast packet 01:80:c2:00:00:1c (1Mbps), all 3 DUT Web GUI can be accessable without hanging.

So appreciate if you could help confirm below?

1> Did you DUTs upgrade to the latest FW? If no, please download center to get

2> What about throughput of broadcast packet 01:80:c2:00:00:1c (generated by AP)?

3> Yous issue is DUT hang without Web access?

4> If possbile, can you help send back config of all DUTs for our further debugging?

How to get config for smart switch GS752TXS and GS728TXS - http://kb.netgear.com/31438/How-do-I-send-diagnostic-files-from-my-Smart-Switch-to-NETGEAR-community-moderators

How to get config for M7100 - http://kb.netgear.com/31439/How-do-I-send-diagnostic-files-from-my-Managed-Switch-to-NETGEAR-community-moderators

elderone

Aspirant

Mar 13, 2017

I do have latest firmware on GS728TXS and GSM7248v2 switches (where AP-s where connected). Other 3 switches are not with the latest firmware.
I don't have LAGs or LACP in use.

During that time when Unifi AP-s where on 3.7 firmware and inaccessible, there was constant 110 Kbit/s traffic from switch port where AP was connected.
Also somewhere in than timeframe my M7100 switch WEB GUI stopped working. Otherwise switching works, snmp monitoring and remote loggin also works. Only web gui won't respond.
Downgraded Unifi firmware back to 3.4 for now.