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New Member

Receiving STP Traffic on each Host.

Hi Team,

I'm getting STP traffic on each host in LAn after every 3-4 sec in wirshark captured snoop.Not understanding whats that traffic.is it affecting netwok performance.

"

15849 384.174829 Cisco_bb:b8:08 Spanning-tree-(for-bridges)_00 STP Conf. Root = 32768/00:01:96:64:ce:67 Cost = 12 Port = 0x8008"

15848 383.490158 Cisco_bb:b8:08 Cisco_bb:b8:08 LOOP Reply

Please advise..

Thanks

Prashant

4 REPLIES
Cisco Employee

Re: Receiving STP Traffic on each Host.

Hello Prashant,

The Spanning Tree Protocol traffic is a necessary traffic of a protocol that prevents Layer2 loops in your network. The STP packets are small and despite being sent out every 2 seconds, you do not have to worry about their bandwidth usage - it is negligible.

Best regards,

Peter

Silver

Re: Receiving STP Traffic on each Host.

I agree, 1 pkt each 2 seconds is nothing to worry about.

I know it scares looking at wireshark and seeing all of those pink packets but keep in mind that in terms of network traffic and link utilization 0.5 pps is insignificant.

Plus the NIC of the PC will drop them because the destination MAC is not known by most PCs and it won't hard its CPU cycles or additional processing

Re: Receiving STP Traffic on each Host.

switch will use spanning-tree protocol to break the layer 2 loop. Thoes should be normal traffic.

New Member

Re: Receiving STP Traffic on each Host.

Hello.

If you really want to get rid of the STP traffic on access ports, you could do the following:

- configure your access ports "switchport mode access"

- enable "spanning-tree portfast" on all your access ports

- globally enable "spanning-tree portfast bpdufilter default"

This will stop the STP traffic on the access ports.

Used this in my network, too.

Regards

Frank

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