示例：在 MX 系列上配置基本 2 层交换
此示例显示了如何配置2 层交换参与单个 VLAN 的所有接口的接口。
要求
配置此示例之前，不需要除设备初始化之外的特殊配置。
此示例使用 MX 系列设备执行2 层交换。
概述
此示例将一个 MX 系列设备配置为基本单 VLAN 交换机。三个连接已就位。来自 MX 系列设备的连接连接到 Junos OS路由器，但此处此路由器仅用于测试目的。您可以用任何 IP 网络设备来交换路由器。
配置
CLI快速配置
要快速配置此示例，请复制以下命令，将其粘贴到文本文件中，删除所有换行符，更改详细信息，以匹配网络配置，然后将命令复制并粘贴到 层次结构级别的 CLI 中 [edit] 。
设备 S1
set interfaces ge-2/0/0 vlan-tagging set interfaces ge-2/0/0 encapsulation extended-vlan-bridge set interfaces ge-2/0/0 unit 0 vlan-id 600 set interfaces ge-2/0/1 vlan-tagging set interfaces ge-2/0/1 encapsulation extended-vlan-bridge set interfaces ge-2/0/1 unit 0 vlan-id 600 set interfaces ge-2/0/2 vlan-tagging set interfaces ge-2/0/2 encapsulation extended-vlan-bridge set interfaces ge-2/0/2 unit 0 vlan-id 600 set bridge-domains customer1 domain-type bridge set bridge-domains customer1 interface ge-2/0/0.0 set bridge-domains customer1 interface ge-2/0/2.0 set bridge-domains customer1 interface ge-2/0/1.0
设备 R1
set interfaces ge-1/3/2 vlan-tagging set interfaces ge-1/3/2 unit 0 vlan-id 600 set interfaces ge-1/3/2 unit 0 family inet address 10.0.0.1/24
设备 R2
set interfaces ge-3/1/0 vlan-tagging set interfaces ge-3/1/0 unit 0 vlan-id 600 set interfaces ge-3/1/0 unit 0 family inet address 10.0.0.2/24
设备 R3
set interfaces ge-2/0/1 vlan-tagging set interfaces ge-2/0/1 unit 0 vlan-id 600 set interfaces ge-2/0/1 unit 0 family inet address 10.0.0.3/24
程序
逐步过程
以下示例要求您在配置层次结构中导航各个级别。有关导航指南CLI，请参阅 CLI用户指南 中的 在配置模式下Junos OS CLI 编辑器。
要配置设备 S1：
配置设备接口。
[edit interfaces] user@S1# set interfaces ge-2/0/0 vlan-tagging user@S1# set interfaces ge-2/0/0 encapsulation extended-vlan-bridge user@S1# set interfaces ge-2/0/0 unit 0 vlan-id 600 user@S1# set interfaces ge-2/0/1 vlan-tagging user@S1# set interfaces ge-2/0/1 encapsulation extended-vlan-bridge user@S1# set interfaces ge-2/0/1 unit 0 vlan-id 600 user@S1# set interfaces ge-2/0/2 vlan-tagging user@S1# set interfaces ge-2/0/2 encapsulation extended-vlan-bridge user@S1# set interfaces ge-2/0/2 unit 0 vlan-id 600
配置桥接域。
[edit interfaces] user@S1# set bridge-domains customer1 domain-type bridge user@S1# set bridge-domains customer1 interface ge-2/0/0.0 user@S1# set bridge-domains customer1 interface ge-2/0/2.0 user@S1# set bridge-domains customer1 interface ge-2/0/1.0
结果
在配置模式下，输入 和 命令以确认 show interfaces show bridge-domains 您的配置。如果输出未显示预期的配置，请重复此示例中的说明，以更正配置。
user@S1# show interfaces
ge-2/0/0 {
vlan-tagging;
encapsulation extended-vlan-bridge;
unit 0 {
vlan-id 600;
}
}
ge-2/0/1 {
vlan-tagging;
encapsulation extended-vlan-bridge;
unit 0 {
vlan-id 600;
}
}
ge-2/0/2 {
vlan-tagging;
encapsulation extended-vlan-bridge;
unit 0 {
vlan-id 600;
}
}
user@S1# show bridge-domains
customer1 {
domain-type bridge;
interface ge-2/0/0.0;
interface ge-2/0/2.0;
interface ge-2/0/1.0;
}
如果完成设备配置，请从配置 commit 模式输入 。
验证
确认配置工作正常。
确认 MAC 地址学习
目的
显示第 2 层MAC 地址信息。
行动
从设备 S1 运行
show bridge mac-table命令。user@S1> show bridge mac-table MAC flags (S -static MAC, D -dynamic MAC, L -locally learned, C -Control MAC SE -Statistics enabled, NM -Non configured MAC, R -Remote PE MAC) Routing instance : default-switch Bridging domain : customer1, VLAN : NA MAC MAC Logical NH RTR address flags interface Index ID 00:12:1e:ee:34:dd D ge-2/0/2.0 00:1d:b5:5e:86:79 D ge-2/0/0.0 00:21:59:0f:35:2b D ge-2/0/1.0从设备 S1 运行
show bridge mac-table extensive命令。user@S1> show bridge mac-table extensive MAC address: 00:12:1e:ee:34:dd Routing instance: default-switch Bridging domain: customer1, VLAN : NA Learning interface: ge-2/0/2.0 Layer 2 flags: in_hash,in_ifd,in_ifl,in_vlan,in_rtt,kernel,in_ifbd Epoch: 1 Sequence number: 0 Learning mask: 0x00000004 MAC address: 00:1d:b5:5e:86:79 Routing instance: default-switch Bridging domain: customer1, VLAN : NA Learning interface: ge-2/0/0.0 Layer 2 flags: in_hash,in_ifd,in_ifl,in_vlan,in_rtt,kernel,in_ifbd Epoch: 1 Sequence number: 0 Learning mask: 0x00000004 MAC address: 00:21:59:0f:35:2b Routing instance: default-switch Bridging domain: customer1, VLAN : NA Learning interface: ge-2/0/1.0 Layer 2 flags: in_hash,in_ifd,in_ifl,in_vlan,in_rtt,kernel,in_ifbd Epoch: 3 Sequence number: 0 Learning mask: 0x00000004
意义
输出显示已学习 MAC 地址。
确保连接的设备可以彼此连接
目的
验证连接性。
行动
user@R1> ping 10.0.0.2 PING 10.0.0.2 (10.0.0.2): 56 data bytes 64 bytes from 10.0.0.2: icmp_seq=0 ttl=64 time=1.178 ms 64 bytes from 10.0.0.2: icmp_seq=1 ttl=64 time=1.192 ms 64 bytes from 10.0.0.2: icmp_seq=2 ttl=64 time=1.149 ms ^C --- 10.0.0.2 ping statistics --- 3 packets transmitted, 3 packets received, 0% packet loss round-trip min/avg/max/stddev = 1.149/1.173/1.192/0.018 ms
user@R1> ping 10.0.0.3 PING 10.0.0.3 (10.0.0.3): 56 data bytes 64 bytes from 10.0.0.3: icmp_seq=0 ttl=64 time=1.189 ms 64 bytes from 10.0.0.3: icmp_seq=1 ttl=64 time=1.175 ms 64 bytes from 10.0.0.3: icmp_seq=2 ttl=64 time=1.178 ms 64 bytes from 10.0.0.3: icmp_seq=3 ttl=64 time=1.133 ms ^C --- 10.0.0.3 ping statistics --- 4 packets transmitted, 4 packets received, 0% packet loss round-trip min/avg/max/stddev = 1.133/1.169/1.189/0.021 ms
user@R2> ping 10.0.0.3 PING 10.0.0.3 (10.0.0.3): 56 data bytes 64 bytes from 10.0.0.3: icmp_seq=0 ttl=64 time=0.762 ms 64 bytes from 10.0.0.3: icmp_seq=1 ttl=64 time=0.651 ms 64 bytes from 10.0.0.3: icmp_seq=2 ttl=64 time=0.722 ms 64 bytes from 10.0.0.3: icmp_seq=3 ttl=64 time=0.705 ms ^C --- 10.0.0.3 ping statistics --- 4 packets transmitted, 4 packets received, 0% packet loss round-trip min/avg/max/stddev = 0.651/0.710/0.762/0.040 ms
意义
输出显示，已连接的设备已建立第 3 层连接，设备 S1 执行透明的第 2 层桥接。
检查桥接域
目的
显示桥接域信息。
行动
user@S1> show bridge domain extensive
Routing instance: default-switch
Bridge domain: customer1 State: Active
Bridge VLAN ID: NA
Interfaces:
ge-2/0/0.0
ge-2/0/1.0
ge-2/0/2.0
Total MAC count: 3
意义
输出显示桥接域处于活动状态。
检查桥接统计信息
目的
显示桥接统计信息。
行动
user@S1> show bridge statistics
Local interface: ge-2/0/0.0, Index: 65543
Broadcast packets: 0
Broadcast bytes : 0
Multicast packets: 80
Multicast bytes : 8160
Flooded packets : 0
Flooded bytes : 0
Unicast packets : 1
Unicast bytes : 64
Current MAC count: 1 (Limit 1024)
Local interface: ge-2/0/2.0, Index: 324
Broadcast packets: 0
Broadcast bytes : 0
Multicast packets: 80
Multicast bytes : 8160
Flooded packets : 1
Flooded bytes : 74
Unicast packets : 52
Unicast bytes : 4332
Current MAC count: 1 (Limit 1024)
Local interface: ge-2/0/1.0, Index: 196613
Broadcast packets: 2
Broadcast bytes : 128
Multicast packets: 0
Multicast bytes : 0
Flooded packets : 1
Flooded bytes : 93
Unicast packets : 51
Unicast bytes : 4249
Current MAC count: 1 (Limit 1024)
意义
输出显示桥接域接口正在发送和接收数据包。
检查桥接泛洪
目的
显示桥接泛洪信息。
行动
user@S1> show bridge flood extensive
Name: __juniper_private1__
CEs: 0
VEs: 0
Name: default-switch
CEs: 3
VEs: 0
Bridging domain: customer1
Flood route prefix: 0x30003/51
Flood route type: FLOOD_GRP_COMP_NH
Flood route owner: __all_ces__
Flood group name: __all_ces__
Flood group index: 1
Nexthop type: comp
Nexthop index: 568
Flooding to:
Name Type NhType Index
__all_ces__ Group comp 562
Composition: split-horizon
Flooding to:
Name Type NhType Index
ge-2/0/0.0 CE ucst 524
ge-2/0/1.0 CE ucst 513
ge-2/0/2.0 CE ucst 523
Flood route prefix: 0x30005/51
Flood route type: FLOOD_GRP_COMP_NH
Flood route owner: __re_flood__
Flood group name: __re_flood__
Flood group index: 65534
Nexthop type: comp
Nexthop index: 565
Flooding to:
Name Type NhType Index
__all_ces__ Group comp 562
Composition: split-horizon
Flooding to:
Name Type NhType Index
ge-2/0/0.0 CE ucst 524
ge-2/0/1.0 CE ucst 513
ge-2/0/2.0 CE ucst 523
意义
如果数据包的目标 MAC 地址 对设备来说未知（即数据包中的目标 MAC 地址 在转发表中没有条目），设备将复制数据包，在桥接域内除数据包到达的接口外的其他接口上发送数据包。这称为 数据包泛洪，是设备的默认行为，用于确定未知目标路由的传出MAC 地址。
检查第 2 层学习
目的
显示所有接口的 2 层学习信息。
行动
user@S1> show l2-learning interface
Routing Instance Name : default-switch
Logical Interface flags (DL -disable learning, AD -packet action drop,
LH - MAC limit hit, DN - Interface Down )
Logical BD MAC STP Logical
Interface Name Limit State Interface flags
ge-2/0/2.0 0
custom.. 1024 Forwarding
Routing Instance Name : default-switch
Logical Interface flags (DL -disable learning, AD -packet action drop,
LH - MAC limit hit, DN - Interface Down )
Logical BD MAC STP Logical
Interface Name Limit State Interface flags
ge-2/0/0.0 0
custom.. 1024 Forwarding
Routing Instance Name : default-switch
Logical Interface flags (DL -disable learning, AD -packet action drop,
LH - MAC limit hit, DN - Interface Down )
Logical BD MAC STP Logical
Interface Name Limit State Interface flags
ge-2/0/1.0 0
custom.. 1024 Forwarding