两组Juniper数据核心通过配置MC-LAG实现防止环路的出现
一、背景
有两组数据核心交换机部署在两个不同的网络机房，目前状态为单模光纤三层网络互连，但是业务部门提出了一个新的网络需求，要把建三个网段、网关启用在A座机房的核心交换机上，C座机房也要使用这三个网段，幸好在同一个园区，可以再部署两根单模光纤，通过打通二层网络的方式实现，如果两个机房在异地就只能通过vpls的方式实现了。
二、网络拓扑
A座核心交换机是两台Juniper的EX9200系列的核心交换机组成的VRRP，C座核心是两台Juniper的
EX9200系列的核心交换机组成的VRRP，新添加的三个网段的网关配置在A座核心上，如果没有配置mc-lag，四台核心组成了环路，通过配置mc-lag，实现防环机制。在汇聚层上由于双线分别上联两台核心交换机，也有环路出现，这儿可以使用Juniper自带的防环配置RTG，而不采用生成树协议。RTG的使用比MC-LAG要简单，但是只有一端为单台设备时才能使用，因此两组核心之间不能使用RTG配置进行防环。
三、配置
1、在A核心交换机上
（1）在主机上
set vlans vlan452 vlan-id 452
set vlans vlan452 l3-interface irb.452
set vlans vlan452 description "XinXiFaBu-VLAN"
set interfaces irb unit 452 family inet address x.x.152.60/26
set interfaces irb unit 452 family inet address x.x.152.60/26 vrrp-group 63 virtual-address x.x.152.62
set interfaces irb unit 452 family inet address x.x.152.60/26 vrrp-group 63 priority 150
set interfaces irb unit 452 family inet address x.x.152.60/26 vrrp-group 63 preempt
set interfaces irb unit 452 family inet address x.x.152.60/26 vrrp-group 63 accept-data
set vlans vlan652 vlan-id 652
set vlans vlan652 l3-interface irb.652
set vlans vlan652 description "HuLianHuTong-VLAN"
set interfaces irb unit 652 family inet address x.x.152.92/27 vrrp-group 64 virtual-address x.x.152.94
set interfaces irb unit 652 family inet address x.x.152.92/27 vrrp-group 64 priority 150
set interfaces irb unit 652 family inet address x.x.152.92/27 vrrp-group 64 preempt
set interfaces irb unit 652 family inet address x.x.152.92/27 vrrp-group 64 accept-data
set vlans vlan752 vlan-id 752
set vlans vlan752 l3-interface irb.752
set vlans vlan752 description "LuBo-VLAN"
set interfaces irb unit 752 family inet address x.x.152.252/25 vrrp-group 65 virtual-address x.x.152.254
set interfaces irb unit 752 family inet address x.x.152.252/25 vrrp-group 65 priority 150
set interfaces irb unit 752 family inet address x.x.152.252/25 vrrp-group 65 preempt
set interfaces irb unit 752 family inet address x.x.152.252/25 vrrp-group 65 accept-data
set protocols iccp peer x.x.x.18 redundancy-group-id-list 4 // 指向A组的备核心
set interfaces ge-3/0/9 ether-options 802.3ad ae4
set interfaces ge-3/0/9 description "To xxx-EX92xx-1_ge-5/0/9" // 指向C组的主核心
set interfaces ae4 vlan-tagging
set interfaces ae4 unit 0 family ethernet-switching interface-mode trunk
set interfaces ae4 unit 0 family ethernet-switching vlan members 452 //新添加的三个网段
set interfaces ae4 unit 0 family ethernet-switching vlan members 652
set interfaces ae4 unit 0 family ethernet-switching vlan members 752
set interfaces ae4 description "To xxx-EX92xx-1-ae1"
set interfaces ae4 aggregated-ether-options lacp active
set interfaces ae4 aggregated-ether-options lacp periodic fast
set interfaces ae4 aggregated-ether-options lacp system-id 00:01:02:03:04:07
set interfaces ae4 aggregated-ether-options lacp admin-key 4
set interfaces ae4 aggregated-ether-options mc-ae mc-ae-id 4
set interfaces ae4 aggregated-ether-options mc-ae redundancy-group 4
set interfaces ae4 aggregated-ether-options mc-ae chassis-id 0
set interfaces ae4 aggregated-ether-options mc-ae mode active-standby
set interfaces ae4 aggregated-ether-options mc-ae status-control active
set interfaces ae4 aggregated-ether-options mc-ae switchover-mode revertive
（2）在备机上
set vlans vlan452 vlan-id 452
set vlans vlan452 l3-interface irb.452
set vlans vlan452 description "XinXiFaBu-VLAN"
set interfaces irb unit 452 family inet address x.x.152.61/26 vrrp-group 63 virtual-address x.x.152.62
set interfaces irb unit 452 family inet address x.x.152.61/26 vrrp-group 63 priority 100
set interfaces irb unit 452 family inet address x.x.152.61/26 vrrp-group 63 accept-data
set vlans vlan652 vlan-id 652
set vlans vlan652 l3-interface irb.652
set vlans vlan652 description "HuLianHuTong-VLAN"
set interfaces irb unit 652 family inet address x.x.152.93/27 vrrp-group 64 virtual-address x.x.152.94
set interfaces irb unit 652 family inet address x.x.152.93/27 vrrp-group 64 priority 100
set interfaces irb unit 652 family inet address x.x.152.93/27 vrrp-group 64 accept-data
set vlans vlan752 vlan-id 752
set vlans vlan752 l3-interface irb.752
set vlans vlan752 description "LuBo-VLAN"
set interfaces irb unit 752 family inet address x.x.152.253/25
set interfaces irb unit 752 family inet address x.x.152.253/25 vrrp-group 65 virtual-address x.x.152.254
set interfaces irb unit 752 family inet address x.x.152.253/25 vrrp-group 65 priority 100
set interfaces irb unit 752 family inet address x.x.152.253/25 vrrp-group 65 accept-data
set protocols iccp peer x.x.x.17 redundancy-group-id-list 4 // 指向A组的主核心
set interfaces ge-3/0/9 description "To xx-C-x-EX92xx-2_ge-5/0/9" // 指向C组的备核心
set interfaces ge-3/0/9 ether-options 802.3ad ae4
set interfaces ae4 description "To xx-C-EX92xx-2-ae1"
set interfaces ae4 vlan-tagging
set interfaces ae4 unit 0 family ethernet-switching interface-mode trunk
set interfaces ae4 unit 0 family ethernet-switching vlan members 452
set interfaces ae4 unit 0 family ethernet-switching vlan members 652
set interfaces ae4 unit 0 family ethernet-switching vlan members 752
set interfaces ae4 aggregated-ether-options lacp active
set interfaces ae4 aggregated-ether-options lacp periodic fast
set interfaces ae4 aggregated-ether-options lacp system-id 00:01:02:03:04:07
set interfaces ae4 aggregated-ether-options lacp admin-key 4
set interfaces ae4 aggregated-ether-options mc-ae mc-ae-id 4
set interfaces ae4 aggregated-ether-options mc-ae redundancy-group 4
set interfaces ae4 aggregated-ether-options mc-ae chassis-id 1
set interfaces ae4 aggregated-ether-options mc-ae mode active-standby
set interfaces ae4 aggregated-ether-options mc-ae status-control standby
2、在C核心交换机上
set interfaces ae1 vlan-tagging
set interfaces ae1 aggregated-ether-options lacp active
set interfaces ae1 aggregated-ether-options lacp periodic fast
3、在汇聚层上
set ethernet-switching-options redundant-trunk-group group RTG-1 interface ge-0/1/0.0 primary
set ethernet-switching-options redundant-trunk-group group RTG-1 interface ge-0/1/1.0
set ethernet-switching-options storm-control interface all