08-14-2002 02:24 AM - last edited on 03-25-2019 02:40 PM by ciscomoderator
I have a problem on cat3550-12G switch.
I have tested the spanning-tree on cat3550-12G.
But, the stp operation is abnormal.
Two switch SW1 and SW2 are connected with two links.
There is no blocking port on any switch.
Two switch think root bridge itself.
Then, I had captured the BPDU frame.
The destination address of BPDU frames is not 0180c2000000.
The first octet is always different.
IOS : c3550-i5q3l2-mz.121-8.EA1c
08-14-2002 04:08 PM
This cannot happen. Please check for any misconfigurations. Upgrade to latest 12.1(9)EA1, and if you still see the issue
08-14-2002 06:07 PM
If I were you, I told as you.
Other people don't believe as you.
First, Also I doubt the configuration as you.
But, the people that have tested cat3550-12G doubt cat3550-12G switch.
Do you see other question on this web about cat3550-12G stp.
This problem is happened already.
If you possible, please test this problem with cat3550-12G.
And then, Let's talk again.
Must be cat3550-12G. not cat3550-12T, other.
The cat3550-12T and cat3550-48G is normal.
Thank you.
08-14-2002 07:02 PM
I set it up here in the lab and STP is working as it's expected to. My lab switches(both 3550-12G) are running 121-9.EA1c. The switches mostly have default config(assigned all interfaces to VLAN 1).
Switch A
switch-A#sh cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
switch-B Gig 0/12 166 S I WS-C3550-1Gig 0/12
switch-B Gig 0/1 166 S I WS-C3550-1Gig 0/1
switch-A#sh spanning-tree root
Root Hello Max Fwd
Vlan Root ID Cost Time Age Dly Root Port
---------------- -------------------- --------- ----- --- --- ------------
VLAN0001 32769 0005.ddc5.6f00 4 2 20 15 Gi0/1
switch-A#sh spanning-tree vlan 1
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0005.ddc5.6f00
Cost 4
Port 1 (GigabitEthernet0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0005.ddc5.8900
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Port ID Designated Port ID
Name Prio.Nbr Cost Sts Cost Bridge ID Prio.Nbr
---------------- -------- --------- --- --------- -------------------- --------
Gi0/1 128.1 4 FWD 0 32769 0005.ddc5.6f00 128.1
Gi0/12 128.12 4 BLK 0 32769 0005.ddc5.6f00 128.12
switch-A#
SWITCH B
switch-B#sh cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
switch-A Gig 0/12 168 S I WS-C3550-1Gig 0/12
switch-A Gig 0/1 168 S I WS-C3550-1Gig 0/1
switch-B#sh spanning-tree root
Root Hello Max Fwd
Vlan Root ID Cost Time Age Dly Root Port
---------------- -------------------- --------- ----- --- --- ------------
VLAN0001 32769 0005.ddc5.6f00 0 2 20 15
switch-B#sh spanning-tree vlan 1
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0005.ddc5.6f00
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0005.ddc5.6f00
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Port ID Designated Port ID
Name Prio.Nbr Cost Sts Cost Bridge ID Prio.Nbr
---------------- -------- --------- --- --------- -------------------- --------
Gi0/1 128.1 4 FWD 0 32769 0005.ddc5.6f00 128.1
Gi0/12 128.12 4 FWD 0 32769 0005.ddc5.6f00 128.12
switch-B#
08-15-2002 04:18 AM
I did more research on this and found a bug which is being worked on for a similar issue. Can you please paste output of sh versions from both the switches.
http://www.cisco.com/cgi-bin/bugtool/onebug.pl?bugid=CSCdy34098
08-15-2002 05:19 AM
Thank you for your help.
I think I need IOS upgrade.
But, I have no switch for lab test.
All switch is working in the field.
Therefore, I will suggest the IOS upgrade from 12.1.8 to 12.1.9EA1c to my customer.
It is strange.
The information of cisco web page recommand IOS 121-8.EA1c for cat3550.
I think it must be corrected.
Thank you very much.
The below is output of show version.
------------------ show version of SW1 ------------------
Cisco Internetwork Operating System Software
IOS (tm) C3550 Software (C3550-I5Q3L2-M), Version 12.1(8)EA1c, RELEASE SOFTWARE
(fc1)
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Fri 15-Feb-02 10:50 by antonino
Image text-base: 0x00003000, data-base: 0x006675E0
ROM: Bootstrap program is C3550 boot loader
sw1 uptime is 40 minutes
System returned to ROM by power-on
System image file is "flash:c3550-i5q3l2-mz.121-8.EA1c/c3550-i5q3l2-mz.121-8.EA1
c.bin"
cisco WS-C3550-12G (PowerPC) processor (revision A0) with 65526K/8192K bytes of
memory.
Processor board ID CAT0625X0AP
Last reset from warm-reset
Bridging software.
Running Layer2/3 Switching Image
Ethernet-controller 1 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 2 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 3 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 4 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 5 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 6 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 7 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 8 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 9 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 10 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 11 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 12 has 1 Gigabit Ethernet/IEEE 802.3 interface
12 Gigabit Ethernet/IEEE 802.3 interface(s)
The password-recovery mechanism is enabled.
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:09:E8:E4:C7:00
Motherboard assembly number: 73-5526-05
Power supply part number: 34-0967-01
Motherboard serial number: CAT06240B08
Power supply serial number: DAB06170HMN
Model revision number: A0
Motherboard revision number: A0
Model number: WS-C3550-12G
System serial number: CAT0625X0AP
Configuration register is 0x10F
------------------ show version of SW2 ------------------
Cisco Internetwork Operating System Software
IOS (tm) C3550 Software (C3550-I5Q3L2-M), Version 12.1(8)EA1c, RELEASE SOFTWARE
(fc1)
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Fri 15-Feb-02 10:50 by antonino
Image text-base: 0x00003000, data-base: 0x006675E0
ROM: Bootstrap program is C3550 boot loader
sw2 uptime is 41 minutes
System returned to ROM by power-on
System image file is "flash:c3550-i5q3l2-mz.121-8.EA1c/c3550-i5q3l2-mz.121-8.EA1
c.bin"
cisco WS-C3550-12G (PowerPC) processor (revision A0) with 65526K/8192K bytes of
memory.
Processor board ID CAT0625X0B0
Last reset from warm-reset
Bridging software.
Running Layer2/3 Switching Image
Ethernet-controller 1 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 2 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 3 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 4 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 5 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 6 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 7 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 8 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 9 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 10 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 11 has 1 Gigabit Ethernet/IEEE 802.3 interface
Ethernet-controller 12 has 1 Gigabit Ethernet/IEEE 802.3 interface
12 Gigabit Ethernet/IEEE 802.3 interface(s)
The password-recovery mechanism is enabled.
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:09:E8:E4:D1:80
Motherboard assembly number: 73-5526-05
Power supply part number: 34-0967-01
Motherboard serial number: CAT06240B0R
Power supply serial number: DAB06170HP7
Model revision number: A0
Motherboard revision number: A0
Model number: WS-C3550-12G
System serial number: CAT0625X0B0
Configuration register is 0x10F
=============================================================
08-15-2002 06:18 AM
This is a similer question.
Aug 1,2002
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LAN, Switching and Routing
Cat 3550-12G and 2950-24G Spanning Tree Root Problem
j.t.faust@worldnet.att.net - SYSTEMS CONSULTANT, COOPER CAMERON
Aug 1, 2002, 8:13am PST
Have a stack of 2950s with a 3550-12G running current IOSs 12.1(9)EA1d and 12.1.(9)EA1c. The 3550 thinks it's the root bridge and all the 2950s think one of the 2950s is the root. I can connect and ping all the mgmt interfaces for all switches, but not any other device on any port. Any suggestions?
Update.. The 2950s do not hear the BPDUs from the 3550.
Thanks
Ted
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tstevens - CISCO SYSTEMS, CCIE
Aug 1, 2002, 10:42am PST (1.)
Possible VLAN mismatch? Unidirectional link? Not enough info here to make more than a wild guess.
========================================================
According to upper, cat3550 IOS is 12.1.(9)EA1c .
That is same IOS with you.
So then, 2950-24G has stp problem ??
I am confused.
08-15-2002 08:23 PM
Please open up the TAC case, for further troubleshooting and narrow down the problem.
08-15-2002 09:18 PM
Ok
I'll do that.
Thank very much for your help.
08-27-2002 03:02 PM
12.1(11)EA1 has a fix for this issue
http://www.cisco.com/cgi-bin/bugtool/onebug.pl?bugid=CSCdy21905
02-28-2018 07:23 PM
STP is using the system mac address, you can see this mac address with show version. But, in practice I saw also the case where each interface from this L3 switch had a mac address and the source mac address of the BPDU was the mac of interface transmiting the BPDU but in the BPDU message was contained the system mac.
When a L3 port is transmiting the packet at L3 it will rewrite the L2 header and depends on the platform it can use system mac, or it's own mac address if the system has a different mac address for each interface.
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