思科Nexus交换机 --- 华为CE6800 STP生成树对接故障
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
[~Huawei-6857]dis stp brief MSTID Port Role STP State Protection Cost Edged0Eth-Trunk101 DESI forwarding none500enable0Eth-Trunk102 DESI forwarding none125enable<Huawei-6857>display stp vlan2ProcessId InstanceId Port Role State ----------------------------------------------------------------------00Eth-Trunk101 DESI forwarding00Eth-Trunk102 DESI forwarding<Huawei-6857>dis stp interface Eth-Trunk101CIST Global Information: Mode :RSTP CIST Bridge :49152.7c33-f906-6881 Config Times :Hello 2s MaxAge 20s FwDly 15s MaxHop20Active Times :Hello 2s MaxAge 20s FwDly 15s MaxHop20CIST 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=500Designated Bridge/Port :49152.7c33-f906-6881 /128.1Port 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 RemHop20TC or TCN send :0 TC or TCN received :0 TC Restriction :False BPDU Sent :0 TCN:0, Config:0, RST:74, MST:0BPDU Received :0 TCN:0, Config:0, RST:0, MST:0Last forwarding time:2026-03-1814:23:16 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
Stp mode vbst Commit3.2 Confirm stp mode
<Huawei-6857>dis stp CIST Global Information: Mode :VBST CIST Bridge :49152.7c33-f906-6881 Config Times :Hello 2s MaxAge 20s FwDly 15s MaxHop20Active Times :Hello 2s MaxAge 20s FwDly 15s MaxHop20CIST 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
<Huawei-6857>display stp vlan2bpdu statistics --------------------------------------------------------------------------- BPDUSent TCN Config RST VLANID Interface BPDUReceived TCN Config RST ---------------------------------------------------------------------------2Eth-Trunk1016006179173001791732Eth-Trunk102179081001790812002---------------------------------------------------------------------------3.4 查看指定vlan的根
<Huawei-6857>display stp vlan2bridge root ------------------------------------------------------------------------------ Hello Max Forward VLANID RootID RootCost Time Age Delay RootPort ------------------------------------------------------------------------------232770.0023-04ee-be6550022015Eth-Trunk101 ------------------------------------------------------------------------------<Huawei-6857>3.5 查看所有vlan的根
<Huawei-6857>dis stp vlan bridge root ------------------------------------------------------------------------------ Hello Max Forward VLANID RootID RootCost Time Age Delay RootPort ------------------------------------------------------------------------------132769.7c33-f906-6881022015232770.0023-04ee-be6550022015Eth-Trunk101432772.0023-04ee-be6550022015Eth-Trunk101532773.0023-04ee-be6550022015Eth-Trunk101632774.0023-04ee-be6550022015Eth-Trunk101732775.0023-04ee-be6550022015Eth-Trunk101832776.0023-04ee-be6550022015Eth-Trunk101932777.0023-04ee-be6550022015Eth-Trunk101 ```3.6 查看指定vlan的端口状态
<Huawei-6857>display stp vlan2information brief -------------------------------------------------------------------------------- VLANID Interface Role STPState Protection Cost Edged --------------------------------------------------------------------------------2Eth-Trunk101 ROOT forwarding none500disable2Eth-Trunk102 DESI forwarding none125disable --------------------------------------------------------------------------------3.7 查看所有vlan的接口状态
<Huawei-6857>display stp vlan information brief -------------------------------------------------------------------------------- VLANID Interface Role STPState Protection Cost Edged --------------------------------------------------------------------------------2Eth-Trunk101 ROOT forwarding none500disable2Eth-Trunk102 DESI forwarding none125disable4Eth-Trunk101 ROOT forwarding none500disable4Eth-Trunk102 DESI forwarding none125disable5Eth-Trunk101 ROOT forwarding none500disable5Eth-Trunk102 DESI forwarding none125disable6Eth-Trunk101 ROOT forwarding none500disable6Eth-Trunk102 DESI forwarding none125disable7Eth-Trunk101 ROOT forwarding none500disable