思科Nexus93180与华为6857（堆叠）2层互联。
STP MODE：
思科：RSTP-PVST
华为：RSTP
STP Priority:
思科：32768
华为：49152
先说结论：思科的RSTP不是标准的RSTP，而是pvst的增强，所以华为侧需要使用VBST对接。
2 故障描述
2端都使用RSTP对接后，根桥选举失败
华为自己为根
Eth-trunk101 正常应该为root
bash
[~Huawei-6857]dis stp brief
MSTID Port Role STP State Protection Cost Edged
0 Eth-Trunk101 DESI forwarding none 500 enable
0 Eth-Trunk102 DESI forwarding none 125 enable
<Huawei-6857>display stp vlan 2
ProcessId InstanceId Port Role State
----------------------------------------------------------------------
0 0 Eth-Trunk101 DESI forwarding
0 0 Eth-Trunk102 DESI forwarding
<Huawei-6857>dis stp interface Eth-Trunk 101
CIST Global Information:
Mode :RSTP
CIST Bridge :49152.7c33-f906-6881
Config Times :Hello 2s MaxAge 20s FwDly 15s MaxHop 20
Active Times :Hello 2s MaxAge 20s FwDly 15s MaxHop 20
CIST Root/ERPC :49152.7c33-f906-6881 / 0 (This bridge is the root)
CIST RegRoot/IRPC :49152.7c33-f906-6881 / 0 (This bridge is the root)
CIST RootPortId :0.0
BPDU-Protection :Disabled
TC or TCN received :0
TC count per hello :0
STP Converge Mode :Normal
Share region-configuration :Enabled
Time since last TC :0 days 0h:0m:0s
Number of TC :0
Topo Change Flag :0
CIST Port Information:
Port Id :1
Port Name :Eth-Trunk101
Port State :Forwarding
Port Protocol :Enabled
Port Role :Designated Port
Port Priority :128
Port Cost(Dot1T) :Config=auto / Active=500
Designated Bridge/Port :49152.7c33-f906-6881 / 128.1
Port Edged :Config=default / Active=enabled
Point-to-point :Config=auto / Active=true
Transit Limit :6 packets/s
Protection Type :None
Port STP Mode :RSTP
Port Protocol Type :Config=auto / Active=dot1s
BPDU Encapsulation :Config=stp / Active=stp
PortTimes :Hello 2s MaxAge 20s FwDly 15s RemHop 20
TC or TCN send :0
TC or TCN received :0
TC Restriction :False
BPDU Sent :0
TCN: 0, Config: 0, RST: 74, MST: 0
BPDU Received :0
TCN: 0, Config: 0, RST: 0, MST: 0
Last forwarding time:2026-03-18 14:23:16
Message Age :0
<Huawei-6857> 从上面看到，收到的BPDU为0
3 Huawei修改为vbst
3.1 Change mode
bash
Stp mode vbst
Commit3.2 Confirm stp mode
bash
<Huawei-6857>dis stp
CIST Global Information:
Mode :VBST
CIST Bridge :49152.7c33-f906-6881
Config Times :Hello 2s MaxAge 20s FwDly 15s MaxHop 20
Active Times :Hello 2s MaxAge 20s FwDly 15s MaxHop 20
CIST Root/ERPC :49152.7c33-f906-6881 / 0 (This bridge is the root)
CIST RegRoot/IRPC :49152.7c33-f906-6881 / 0 (This bridge is the root)
CIST RootPortId :0.0
BPDU-Protection :Disabled
TC or TCN received :0
TC count per hello :0
STP Converge Mode :Normal
Share region-configuration :Enabled
Time since last TC :0 days 0h:0m:0s
Number of TC :0
Topo Change Flag :0
<Huawei-6857>3.3 Check bpdu statistics
bash
<Huawei-6857>display stp vlan 2 bpdu statistics
---------------------------------------------------------------------------
BPDUSent TCN Config RST
VLANID Interface BPDUReceived TCN Config RST
---------------------------------------------------------------------------
2 Eth-Trunk101 6 0 0 6
179173 0 0 179173
2 Eth-Trunk102 179081 0 0 179081
2 0 0 2
---------------------------------------------------------------------------3.4 查看指定vlan的根
bash
<Huawei-6857>display stp vlan 2 bridge root
------------------------------------------------------------------------------
Hello Max Forward
VLANID RootID RootCost Time Age Delay RootPort
------------------------------------------------------------------------------
2 32770.0023-04ee-be65 500 2 20 15 Eth-Trunk101
------------------------------------------------------------------------------
<Huawei-6857>3.5 查看所有vlan的根
bash
<Huawei-6857> dis stp vlan bridge root
------------------------------------------------------------------------------
Hello Max Forward
VLANID RootID RootCost Time Age Delay RootPort
------------------------------------------------------------------------------
1 32769.7c33-f906-6881 0 2 20 15
2 32770.0023-04ee-be65 500 2 20 15 Eth-Trunk101
4 32772.0023-04ee-be65 500 2 20 15 Eth-Trunk101
5 32773.0023-04ee-be65 500 2 20 15 Eth-Trunk101
6 32774.0023-04ee-be65 500 2 20 15 Eth-Trunk101
7 32775.0023-04ee-be65 500 2 20 15 Eth-Trunk101
8 32776.0023-04ee-be65 500 2 20 15 Eth-Trunk101
9 32777.0023-04ee-be65 500 2 20 15 Eth-Trunk101
```3.6 查看指定vlan的端口状态
bash
<Huawei-6857>display stp vlan 2 information brief
--------------------------------------------------------------------------------
VLANID Interface Role STPState Protection Cost Edged
--------------------------------------------------------------------------------
2 Eth-Trunk101 ROOT forwarding none 500 disable
2 Eth-Trunk102 DESI forwarding none 125 disable
--------------------------------------------------------------------------------3.7 查看所有vlan的接口状态
bash
<Huawei-6857>display stp vlan information brief
--------------------------------------------------------------------------------
VLANID Interface Role STPState Protection Cost Edged
--------------------------------------------------------------------------------
2 Eth-Trunk101 ROOT forwarding none 500 disable
2 Eth-Trunk102 DESI forwarding none 125 disable
4 Eth-Trunk101 ROOT forwarding none 500 disable
4 Eth-Trunk102 DESI forwarding none 125 disable
5 Eth-Trunk101 ROOT forwarding none 500 disable
5 Eth-Trunk102 DESI forwarding none 125 disable
6 Eth-Trunk101 ROOT forwarding none 500 disable
6 Eth-Trunk102 DESI forwarding none 125 disable
7 Eth-Trunk101 ROOT forwarding none 500 disable