Spanning-tree wireshark question

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Aug 4th, 2008
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I am seeing the following lines in Wireshark, but the priority I am seeing is that of the root bridge. Does it matter that I am seeing these wireshark captures on my access switches?


27 8.367618 Cisco_0a:ff:96 Cisco_0a:ff:96 LOOP Reply

28 10.000372 Cisco_0a:ff:96 Spanning-tree-(for-bridges)_00 STP RST. Root = 8192/00:d0:02:d5:74:15 Cost = 23 Port = 0x8016

29 12.000442 Cisco_0a:ff:96 Spanning-tree-(for-bridges)_00 STP RST. Root = 8192/00:d0:02:d5:74:15 Cost = 23 Port = 0x8016

30 14.000520 Cisco_0a:ff:96 Spanning-tree-(for-bridges)_00 STP RST. Root = 8192/00:d0:02:d5:74:15 Cost = 23 Port = 0x8016

31 16.000604 Cisco_0a:ff:96 Spanning-tree-(for-bridges)_00 STP RST. Root = 8192/00:d0:02:d5:74:15 Cost = 23 Port = 0x8016

32 18.000688 Cisco_0a:ff:96 Spanning-tree-(for-bridges)_00 STP RST. Root = 8192/00:d0:02:d5:74:15 Cost = 23 Port = 0x8016

33 18.367969 Cisco_0a:ff:96 Cisco_0a:ff:96 LOOP Reply

Correct Answer by Francois Tallet about 8 years 9 months ago

No, just because STP is running on the access ports;-) Looks perfectly normal.

Regards,

Francois

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massimiliano.se... Mon, 08/04/2008 - 05:35
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Hi,

This is because spanning-tree is enabled on access port too.


In hope this helps.

Best regards.

Massimiliano.

Jason Fraioli Mon, 08/04/2008 - 05:43
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Would these captures be the result of Portfast/BPDUguard running?

Correct Answer
Francois Tallet Mon, 08/04/2008 - 09:14
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No, just because STP is running on the access ports;-) Looks perfectly normal.

Regards,

Francois

bmbreer Mon, 08/04/2008 - 10:26
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It's normal. STP is sent via a multicast MAC address so all hosts on the network will see the STP messages assuming it's not disabled for that broadcast domain.

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