当 Keepalive 会话状态关闭时，Dell Networking SONiC MC-LAG 将受到影响

Summary: 本文介绍当 SONiC 中的 keepalive 会话状态下降时 MC-LAG 如何受到影响。

Affected Products

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Symptoms

当 SONiC 中的 keepalive 会话状态下降时，MC-LAG 会受到影响。
在 keepalive 会话关闭时，会看到以下 MC-LAG 状态：

SONIC-1# show mclag brief
 
Domain ID            : 1
Role                 : active
Session Status       : down
Peer Link Status     : up
Source Address       : 192.168.2.1
Peer Address         : 192.168.2.2
Peer Link            : PortChannel100
Keepalive Interval   : 1 secs
Session Timeout      : 30 secs
Delay Restore        : 300 secs
System Mac           : XX:XX:XX:XX:XX:XX
Mclag System Mac     : 00:00:00:00:00:01
 
 
Number of MLAG Interfaces:1
-----------------------------------------------------------
MLAG Interface       Local/Remote Status 
-----------------------------------------------------------
PortChannel1             up/unknown

Cause

当 SONiC 中的 keepalive 会话状态下降时，MC-LAG 会受到影响。SONiC 中的 keepalive 配置了 IPv4 L3 通信，类似于 OS9 和 OS10 中的备份链路，这通常不会影响 VLT-Portchannel 状态。OS9 和 OS10 中的对等链路状态将改为影响 VLT-Portchannel 状态。但是，在 SONiC 中，keepalive 会话状态必须处于正常运行状态，MC-LAG 才能正常运行。对于 keepalive 链路，在 MC-LAG 对等设备之间传输定期心跳信号，还用于同步 MC-LAG 对等设备之间的状态。与 SONiC 不同，OS9 和 OS10 使用对等链路在 VLT 对等设备之间同步状态。

MCLAG 术语描述

当 keepalive 会话链路关闭后，由于两个对等设备之间的同步失败，两个 MC-LAG 对等设备上的 MC-LAG 状态将变为正常运行/未知。

处于正常状态

SONIC-1#show version 
 
Software Version  : 4.1.0-Enterprise_Base
Product           : Enterprise SONiC Distribution by Dell Technologies
Distribution      : Debian 10.13
Kernel            : 5.10.0-8-2-amd64
Config DB Version : version_4_1_1
Build Commit      : 93589a15db
Build Date        : Tue Apr 18 17:56:48 UTC 2023
Built By          : sonicbld@sonic-lvn-csg-001
Platform          : x86_64-kvm_x86_64-r0
HwSKU             : DellEMC-S5248f-P-25G-DPB

SONIC-1# show ip interfaces 
Flags: U-Unnumbered interface, A-Anycast IP
-----------------------------------------------------------------------------------------------------------------
Interface            IP address/mask                              VRF                 Admin/Oper     Flags          
-----------------------------------------------------------------------------------------------------------------
PortChannel200       192.168.2.1/24                                                   up/up                         
Vlan636              172.16.0.1/24                                                    up/up                         
SONIC-1# 
SONIC-1# 
SONIC-1# show PortChannel summary 
Flags(oper-status):  D - Down U - Up (portchannel) P - Up in portchannel (members)
----------------------------------------------------------------------------------------------------------------------------
Group               PortChannel                   Type                Protocol          Member Ports
----------------------------------------------------------------------------------------------------------------------------
1                   PortChannel1   (U)            Eth                 LACP                 Eth1/1(P)
100                 PortChannel100 (U)            Eth                 NONE                 Eth1/8(P)
                                                                                           Eth1/9(P)
200                 PortChannel200 (U)            Eth                 LACP                 Eth1/5(P)
                                                                                           Eth1/6(P)
SONIC-1# 
SONIC-1# 
SONIC-1# show mclag brief
 
Domain ID            : 1
Role                 : active
Session Status       : up
Peer Link Status     : up
Source Address       : 192.168.2.1
Peer Address         : 192.168.2.2
Peer Link            : PortChannel100
Keepalive Interval   : 1 secs
Session Timeout      : 30 secs
Delay Restore        : 300 secs
System Mac           : XX:XX:XX:XX:XX:XX
Mclag System Mac     : 00:00:00:00:00:01
 
 
Number of MLAG Interfaces:1
-----------------------------------------------------------
MLAG Interface       Local/Remote Status 
-----------------------------------------------------------
PortChannel1             up/up
SONIC-1# 
SONIC-1# 
SONIC-1# show running-configuration interface PortChannel 1
!
interface PortChannel1 mode active
 switchport trunk allowed Vlan 636
 no shutdown
 mclag 1
SONIC-1# show running-configuration interface PortChannel 100
!
interface PortChannel100 mode on
 switchport trunk allowed Vlan 1-4094
 no shutdown
SONIC-1# show running-configuration interface PortChannel 200
!
interface PortChannel200 mode active
 no shutdown
 ip address 192.168.2.1/24
SONIC-1# 
SONIC-1# 
SONIC-1# ping 172.16.0.3  //IP address assigned to VLAN636 on uplink SW.
PING 172.16.0.3 (172.16.0.3) 56(84) bytes of data.
64 bytes from 172.16.0.3: icmp_seq=1 ttl=64 time=3.26 ms
64 bytes from 172.16.0.3: icmp_seq=2 ttl=64 time=3.47 ms
64 bytes from 172.16.0.3: icmp_seq=3 ttl=64 time=3.21 ms
64 bytes from 172.16.0.3: icmp_seq=4 ttl=64 time=2.84 ms
64 bytes from 172.16.0.3: icmp_seq=5 ttl=64 time=11.1 ms
^C
SONIC-1#

SONIC-2#show version 
 
Software Version  : 4.1.0-Enterprise_Base
Product           : Enterprise SONiC Distribution by Dell Technologies
Distribution      : Debian 10.13
Kernel            : 5.10.0-8-2-amd64
Config DB Version : version_4_1_1
Build Commit      : 93589a15db
Build Date        : Tue Apr 18 17:56:48 UTC 2023
Built By          : sonicbld@sonic-lvn-csg-001
Platform          : x86_64-kvm_x86_64-r0
HwSKU             : DellEMC-S5248f-P-25G-DPB

SONIC-2# show ip interfaces 
Flags: U-Unnumbered interface, A-Anycast IP
-----------------------------------------------------------------------------------------------------------------
Interface            IP address/mask                              VRF                 Admin/Oper     Flags          
-----------------------------------------------------------------------------------------------------------------
PortChannel200       192.168.2.2/24                                                   up/up                         
Vlan636              172.16.0.2/24                                                    up/up                         
SONIC-2# 
SONIC-2# 
SONIC-2# show PortChannel summary 
Flags(oper-status):  D - Down U - Up (portchannel) P - Up in portchannel (members)
----------------------------------------------------------------------------------------------------------------------------
Group               PortChannel                   Type                Protocol          Member Ports
----------------------------------------------------------------------------------------------------------------------------
1                   PortChannel1   (U)            Eth                 LACP                 Eth1/1(P)
100                 PortChannel100 (U)            Eth                 NONE                 Eth1/8(P)
                                                                                           Eth1/9(P)
200                 PortChannel200 (U)            Eth                 LACP                 Eth1/5(P)
                                                                                           Eth1/6(P)
SONIC-2# 
SONIC-2# 
SONIC-2# show mclag brief
 
Domain ID            : 1
Role                 : standby
Session Status       : up
Peer Link Status     : up
Source Address       : 192.168.2.2
Peer Address         : 192.168.2.1
Peer Link            : PortChannel100
Keepalive Interval   : 1 secs
Session Timeout      : 30 secs
Delay Restore        : 300 secs
System Mac           : XX:XX:XX:XX:XX:XX
Mclag System Mac     : 00:00:00:00:00:01
 
 
Number of MLAG Interfaces:1
-----------------------------------------------------------
MLAG Interface       Local/Remote Status 
-----------------------------------------------------------
PortChannel1             up/up
SONIC-2# 
SONIC-2# 
SONIC-2# 
SONIC-2# 
SONIC-2# show running-configuration interface PortChannel 1
!
interface PortChannel1 mode active
 switchport trunk allowed Vlan 636
 no shutdown
 mclag 1
SONIC-2# show running-configuration interface PortChannel 100
!
interface PortChannel100 mode on
 switchport trunk allowed Vlan 1-4094
 no shutdown
SONIC-2# show running-configuration interface PortChannel 200
!
interface PortChannel200 mode active
 no shutdown
 ip address 192.168.2.2/24
SONIC-2# 
SONIC-2# 
SONIC-2# ping 172.16.0.3
PING 172.16.0.3 (172.16.0.3) 56(84) bytes of data.
64 bytes from 172.16.0.3: icmp_seq=1 ttl=64 time=3.48 ms
64 bytes from 172.16.0.3: icmp_seq=2 ttl=64 time=2.94 ms
^CSONIC-2#

处于问题状态（通过关闭 Po200 成员端口关闭 Keepalive-link 状态）

SONIC-1# show mclag brief
 
Domain ID            : 1
Role                 : active
Session Status       : down
Peer Link Status     : up
Source Address       : 192.168.2.1
Peer Address         : 192.168.2.2
Peer Link            : PortChannel100
Keepalive Interval   : 1 secs
Session Timeout      : 30 secs
Delay Restore        : 300 secs
System Mac           : XX:XX:XX:XX:XX:XX
Mclag System Mac     : 00:00:00:00:00:01
 
 
Number of MLAG Interfaces:1
-----------------------------------------------------------
MLAG Interface       Local/Remote Status 
-----------------------------------------------------------
PortChannel1             up/unknown
SONIC-1# 
SONIC-1# 
SONIC-1# ping 172.16.0.3
PING 172.16.0.3 (172.16.0.3) 56(84) bytes of data.
64 bytes from 172.16.0.3: icmp_seq=1 ttl=64 time=8.00 ms
64 bytes from 172.16.0.3: icmp_seq=2 ttl=64 time=3.08 ms
64 bytes from 172.16.0.3: icmp_seq=3 ttl=64 time=2.99 ms
64 bytes from 172.16.0.3: icmp_seq=4 ttl=64 time=2.92 ms
64 bytes from 172.16.0.3: icmp_seq=5 ttl=64 time=3.07 ms
^C
SONIC-1#

SONIC-2# show PortChannel summary 
Flags(oper-status):  D - Down U - Up (portchannel) P - Up in portchannel (members)
----------------------------------------------------------------------------------------------------------------------------
Group               PortChannel                   Type                Protocol          Member Ports
----------------------------------------------------------------------------------------------------------------------------
1                   PortChannel1   (U)            Eth                 LACP                 Eth1/1(P)
100                 PortChannel100 (U)            Eth                 NONE                 Eth1/8(P)
                                                                                           Eth1/9(P)
200                 PortChannel200 (D)            Eth                 LACP                 Eth1/5(D)
                                                                                          Eth1/6(D)
SONIC-2# show mclag brief
 
Domain ID            : 1
Role                 : standby
Session Status       : down
Peer Link Status     : up
Source Address       : 192.168.2.2
Peer Address         : 192.168.2.1
Peer Link            : PortChannel100
Keepalive Interval   : 1 secs
Session Timeout      : 30 secs
Delay Restore        : 300 secs
System Mac           : XX:XX:XX:XX:XX:XX
Mclag System Mac     : 00:00:00:00:00:01
 
 
Number of MLAG Interfaces:1
-----------------------------------------------------------
MLAG Interface       Local/Remote Status 
-----------------------------------------------------------
PortChannel1             up/unknown
SONIC-2# 
SONIC-2# ping 172.16.0.3
PING 172.16.0.3 (172.16.0.3) 56(84) bytes of data.
From 172.16.0.2 icmp_seq=1 Destination Host Unreachable
From 172.16.0.2 icmp_seq=1 Destination Host Unreachable
From 172.16.0.2 icmp_seq=1 Destination Host Unreachable
From 172.16.0.2 icmp_seq=1 Destination Host Unreachable
^C

Resolution

为了使 MC-LAG 保持正常运行，而不会出现任何问题，keepalive 链路状态还必须保持正常运行。管理端口通常用于 keepalive 链路，但分配有 IP 地址的端口通道可用于 keepalive 链路以实现冗余目的。本知识库文章中所述的行为（当 keepalive 链路状态停止时 MC-LAG 将受到影响），至少在 SONiC 版本 4.2.0 之前，应在所有版本中进行描述。

Affected Products

Enterprise SONiC Distribution, Dell EMC Networking N3200-ON, PowerSwitch S5212F-ON, PowerSwitch S5224F-ON, PowerSwitch S5232F-ON, PowerSwitch S5248F-ON, PowerSwitch S5296F-ON, PowerSwitch Z9100-ON, PowerSwitch Z9264F-ON, PowerSwitch Z9332F-ON

Article Number: 000213968

Article Type: Solution

Last Modified: 23 Jan 2024

Version: 3

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当 Keepalive 会话状态关闭时，Dell Networking SONiC MC-LAG 将受到影响

Summary: 本文介绍当 SONiC 中的 keepalive 会话状态下降时 MC-LAG 如何受到影响。

Symptoms

Cause

Resolution

Affected Products

Symptoms

Cause

Resolution

Affected Products

Article Properties

Find answers to your questions from other Dell users

Support Services

Article Properties

Find answers to your questions from other Dell users

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当 Keepalive 会话状态关闭时，Dell Networking SONiC MC-LAG 将受到影响

Summary: 本文介绍当 SONiC 中的 keepalive 会话状态下降时 MC-LAG 如何受到影响。

Detailed Article

Symptoms

Cause

Resolution

Affected Products

Symptoms

Cause

Resolution

Affected Products

Article Properties

Find answers to your questions from other Dell users

Support Services

Article Properties

Find answers to your questions from other Dell users

Support Services