排除ACI vPC故障
简介
本文档介绍确定ACI上的虚拟端口通道(vPC)通信问题所需的命令。
先决条件
要求
本文档没有任何特定的要求。
使用的组件
本文档不限于特定的软件和硬件版本。
本文档中的信息都是基于特定实验室环境中的设备编写的。本文档中使用的所有设备最初均采用原始（默认）配置。如果您的网络处于活动状态，请确保您了解所有命令的潜在影响。
背景信息
以应用为中心的基础设施(ACI)和对等设备之间的vPC必须已启动且运行正常，且没有配置问题。
配置
拓扑说明
ACI枝叶1：接口Ethernet 1/1、端口通道5和vPC 343。
ACI枝叶2：接口Ethernet 1/2、端口通道5和vPC 343。
NX-OS 1：接口Ethernet 1/1和Ethernet 1/2、端口通道14和vPC 45。
连接:
枝叶1 Eth1/1 <-> NX-OS 1 Eth1/1
枝叶2 Eth1/2 <-> NX-OS 1 Eth1/2
网络图
验证
使用本部分可确认配置能否正常运行。
思科 CLI 分析器（仅适用于注册客户）支持某些 show 命令。使用Cisco CLI分析器查看show命令输出的分析。
使用命令show vpc brief vpc x您可以看到vPC的状态（打开/关闭）。
LEAF1#show vpc brief vpc 343 vPC status ---------------------------------------------------------------------- id Port Status Consistency Reason Active vlans -- ---- ------ ----------- ------ ------------ 343 Po5 up success success 100
LEAF2#show vpc brief vpc 343 vPC status ---------------------------------------------------------------------- id Port Status Consistency Reason Active vlans -- ---- ------ ----------- ------ ------------ 343 Po5 up success success 100
使用命令 show port-channel summary interface port-channel x 您可以看到端口通道的状态(Up/Down)、当前标志和配置它的物理接口。
LEAF1#show port-channel summary interface port-channel 5
Flags: D - Down P - Up in port-channel (members)
I - Individual H - Hot-standby (LACP only)
s - Suspended r - Module-removed
S - Switched R - Routed
U - Up (port-channel)
M - Not in use. Min-links not met
F - Configuration failed
-------------------------------------------------------------------------------
Group Port- Type Protocol Member Ports
Channel
-------------------------------------------------------------------------------
5 Po5(SU) Eth LACP Eth1/1(P)
LEAF2#show port-channel summary interface port-channel 5
Flags: D - Down P - Up in port-channel (members)
I - Individual H - Hot-standby (LACP only)
s - Suspended r - Module-removed
S - Switched R - Routed
U - Up (port-channel)
M - Not in use. Min-links not met
F - Configuration failed
-------------------------------------------------------------------------------
Group Port- Type Protocol Member Ports
Channel
-------------------------------------------------------------------------------
5 Po5(SU) Eth LACP Eth1/2(P)
故障排除
本节提供可用于对配置进行故障排除的信息。
电缆错误问题
在APIC GUI上，您必须看到以下故障：
Fault F0518: A configuration is not consistent with peer node. Misconfigured due to vPC link in the 2 switches connected to different partners.
ACI枝叶1：接口Ethernet 1/1、端口通道5和vPC 343。
ACI枝叶2：接口Ethernet 1/2、端口通道5和vPC 343。
NXOS 1：接口Ethernet 1/1和Ethernet 1/2，端口通道14和vPC 45。
连接:
枝叶1 Eth1/1 <-> NXOS 1 Eth1/1
枝叶2 Eth1/2 <-> NXOS 1 Eth1/2
如果遇到此问题，输出将如下所示：
LEAF1#show vpc brief vpc 343 vPC status ---------------------------------------------------------------------- id Port Status Consistency Reason Active vlans -- ---- ------ ----------- ------ ------------ 343 Po5 up failed vpc port 100
channel
mis-config
due to vpc
links in the
2 switches
connected to
different
partners
LEAF2#show vpc brief vpc 343 vPC status ---------------------------------------------------------------------- id Port Status Consistency Reason Active vlans -- ---- ------ ----------- ------ ------------ 343 Po5 up failed vpc port 100
channel
mis-config
due to vpc
links in the
2 switches
connected to
different
partners
LEAF1#show port-channel summary interface port-channel 5
Flags: D - Down P - Up in port-channel (members)
I - Individual H - Hot-standby (LACP only)
s - Suspended r - Module-removed
S - Switched R - Routed
U - Up (port-channel)
M - Not in use. Min-links not met
F - Configuration failed
-------------------------------------------------------------------------------
Group Port- Type Protocol Member Ports
Channel
-------------------------------------------------------------------------------
5 Po5(SD) Eth LACP Eth1/1(D)
LEAF2#show port-channel summary interface port-channel 5
Flags: D - Down P - Up in port-channel (members)
I - Individual H - Hot-standby (LACP only)
s - Suspended r - Module-removed
S - Switched R - Routed
U - Up (port-channel)
M - Not in use. Min-links not met
F - Configuration failed
-------------------------------------------------------------------------------
Group Port- Type Protocol Member Ports
Channel
-------------------------------------------------------------------------------
5 Po5(SD) Eth LACP Eth1/2(D)
LEAF1# show lacp interface ethernet 1/1 | grep Lag
Lag Id: [ [(7f9b, 0-11-1-aa-aa-aa, 8157, 8000, 10d), (8000, 0-22-2-bb-bb-bb, 65, 8000, 125)] ]LEAF2# show lacp interface ethernet 1/2 | grep Lag
Lag Id: [ [(7f9b, 0-11-1-aa-aa-aa, 8157, 8000, 10d), (8000, 0-33-3-cc-cc-cc, 65, 8000, 125)] ]连接的设备延迟信息（输出命令中的第二个矢量）在两个输出上必须相同。同样，矢量1在两者上必须相同。
下一步：
如果您有此行为，则必须检查物理连接，以确保端口上的连接尚未交换。
检测到单个端口（按环路）
在APIC GUI上，您必须看到以下故障：
Fault F2705: A vPC interface goes down while peer interface is up.
Fault F2533: A loop was detected by the MCP protocol on ACI.
此问题影响在对等设备上运行STP协议的vPC拓扑。
ACI枝叶1：接口Ethernet 1/1和Ethernet 1/2，端口通道5和vPC 343
NXOS 1：接口Ethernet 1/1、Port-Channel 14和vPC 45
NXOS 2：接口Ethernet 1/2、端口通道14和vPC 45
连接:
枝叶1 Eth1/1 <-> NXOS 1 Eth1/1
枝叶1 Eth1/2 <-> NXOS 2 Eth1/2
对于此故障排除步骤，了解MisCabling Protocol(MCP)的概念非常重要。
MCP检测来自外部源的环路(服务器、使用STP的外部网络设备的错误行为等)，并错误禁用ACI接收其自身数据包的接口。
要了解有关MCP的详细信息，请参阅：对ACI使用MCP。
如果存在此问题，输出如下所示：
LEAF2#show mcp internal info interface eth 1/2
------------------------------------------
Interface: Ethernet1/2
Native PI VLAN: 100
Native Encap VLAN: 1
BPDU Guard: disabled
BPDU Filter: disabled
Port State: down
Layer3 Port: false
Switching State: enabled
Mac Address: AA:AA:AA:AA:AA:01
Interface MCP enabled: true
------------------- STP STATS --------------------
MSTP Count: 0
RSTP Count: 4
MSTP TC Count: 0
RSTP TC Count: 4
PVRSTP TC Count: 4
TCN Count: 0
PVID Error BPDU Count: 5
Error Packet Count: 0
BPDU Guard Event Count: 0
--------------- LOOP-DETECTION STATS ---------------
MCP packets sent(Per-vlan): 1278
MCP packets received: 23
MCP invalid packets received: 19
MCP packets received with invalid digest: 0
MCP packets received when switching state is disabled: 0
Interface is a member of port-channel
Number of active VLANs: 1
Number of VLANS in MCP packets are sent: 1
MCP enabled vlans:
628
MCP loop detected at: Tue Jul 19 09:34:46 2022
MCP loop detected in VLAN: 100
-------------- MCP Remote Peer Info --------------
No remote peers exist
一旦解决了环路问题，并且物理接口处于工作状态，但vPC接口继续运行，其中有一个接口处于关闭状态，另一个接口处于单独状态：
LEAF1#show port-channel summary interface port-channel 5
Flags: D - Down P - Up in port-channel (members)
I - Individual H - Hot-standby (LACP only)
s - Suspended r - Module-removed
S - Switched R - Routed
U - Up (port-channel)
M - Not in use. Min-links not met
F - Configuration failed
-------------------------------------------------------------------------------
Group Port- Type Protocol Member Ports
Channel
-------------------------------------------------------------------------------
5 Po5(SD) Eth LACP Eth1/1(I)
LEAF2#show port-channel summary interface port-channel 5
Flags: D - Down P - Up in port-channel (members)
I - Individual H - Hot-standby (LACP only)
s - Suspended r - Module-removed
S - Switched R - Routed
U - Up (port-channel)
M - Not in use. Min-links not met
F - Configuration failed
-------------------------------------------------------------------------------
Group Port- Type Protocol Member Ports
Channel
-------------------------------------------------------------------------------
5 Po5(SD) Eth LACP Eth1/2(D)
下一步：
确保端口通道配置在两端正确，且通道捆绑正确。
如果两端配置正确并且在环路之前运行良好，请尝试以下操作：
导航至：
Fabric -> Inventory -> Pod -> Leaf x -> Interfaces -> VPC interfaces -> vpc -> Port-channel interface where is included the physical port 1/x -> right-click and select Disable.
然后等待10秒，右键单击并选择Enable.
这些步骤必须在受影响的接口上执行，以强制端口通道与对等设备同步，而且此过程之后必须正常运行。
接口更改为运行关闭
在APIC GUI上，您必须看到以下故障：
Fault F1296: A vPC interface goes down while peer interface is also down.
此示例说明接口必须如何显示信息：
Leaf1# show interface port-channel 5
port-channel5 is down (port-channel-members-down)
admin state is up
Hardware: Port-Channel, address: xxxx.xxxx.xx01 (bia xxxx.xxxx.xx01)
MTU 9000 bytes, BW 100000000 Kbit, DLY 1 usec
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, medium is broadcast
Port mode is trunk
full-duplex, 100 Gb/s
Input flow-control is off, output flow-control is off
Auto-mdix is turned on
EtherType is 0x8100
Members in this channel: eth1/1
您必须查看并放弃以下主题：
- 物理问题（收发器和电缆）必须是进行检查的第一步。
- 两端配置更改。
- 在枝叶接口上收到了链路汇聚控制协议(LACP)信息。
LACP日志
您可以使用命令show lacp internal event-history interface ethernet 1/x要获取与LACP状态相关的事件，如以下示例：
Leaf1#show lacp internal event-history interface ethernet 1/1
Output omitted
...
9) FSM:<Ethernet1/1> Transition at 2022-07-15T08:43:06.121732000+00:00
Previous state: [LACP_ST_DETACHED_LAG_NOT_DETERMINED]
Triggered event: [LACP_EV_RECEIVE_PARTNER_PDU_TIMED_OUT_II_INDIVIDUAL]
Next state: [LACP_ST_INDIVIDUAL_OR_DEFAULT]
Output omitted
...
18) FSM:<Ethernet1/1> Transition at 2022-07-15T08:46:24.298022000+00:00
Previous state: [LACP_ST_DETACHED_LAG_NOT_DETERMINED]
Triggered event: [LACP_EV_RECEIVE_PARTNER_PDU_TIMED_OUT]
Next state: [FSM_ST_NO_CHANGE]
Output omitted
...
23) FSM:<Ethernet1/1> Transition at 2022-07-15T08:46:27.299819000+00:00
Previous state: [LACP_ST_DETACHED_LAG_NOT_DETERMINED]
Triggered event: [LACP_EV_RECEIVE_PARTNER_PDU_TIMED_OUT_II_INDIVIDUAL]
Next state: [LACP_ST_INDIVIDUAL_OR_DEFAULT]
Output omitted
...
24) FSM:<Ethernet1/1> Transition at 2022-07-15T08:52:25.204611000+00:00
Previous state: [LACP_ST_INDIVIDUAL_OR_DEFAULT]
Triggered event: [LACP_EV_LACP_DOWN_OR_PORT_DOWN]
Next state: [LACP_ST_PORT_IS_DOWN_OR_LACP_IS_DISABLED]
示例日志显示ACI未收到来自对等设备的正确应答，在某些情况下，在保活计时器到期之前，对等设备不会发送PDU/LACP。
下一步：
现在，您需要检验对等设备的配置和状态。
思科 CLI 分析器（仅适用于注册客户）支持某些 show 命令。使用Cisco CLI分析器查看show命令输出的分析。
相关信息
修订历史记录
| 版本 | 发布日期 | 备注 |
|---|---|---|
1.0 |
17-Oct-2022 |
初始版本 |
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