示例：配置 BGP 大型社区
此示例说明如何配置可选的传递路径属性 - 一个 12 字节 BGP 大型社区，它提供最重要的 4 字节值以作为全局管理员对自治系统编号进行编码，并提供其余两个 4 字节分配的编号来对 RFC 8092 中定义的本地值进行编码。可以在层次结构级别配置 [edit routing-options static route ip-address community] BGP 大型社区[edit policy-options community community-name members]。BGP 大型社区属性格式有四个字段：large：global administrator:assigned number:assigned number.
要求
此示例使用以下硬件和软件组件：
三个 MX 系列路由器
在所有设备上运行的 Junos OS 17.3 或更高版本
配置此示例之前，不需要除设备初始化之外的特殊配置。
概述
在此示例中，设备 R1 和设备 R2 是自治系统 (AS) 64510 中的 OSPF 邻接方。设备 R3 具有到设备 R1 的外部 BGP （EBGP） 连接。设备 R2 在 172.16/16 地址空间中具有客户网络，使用其环路接口 （lo0） 上的地址进行模拟。设备 R1 具有到多个 172.16.x/24 网络的静态路由，并将常规社区值附加到这些路由。然后，设备 R1 使用导出策略将路由通告到设备 R3。设备 R3 接收这些路由，并使用导入策略向路由添加大型社区值。
拓扑学
图 1 显示了示例网络。
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，更改任何必要的详细信息以匹配您的网络配置，然后将命令复制并粘贴到 [edit] 层次结构级别的 CLI 中。
设备 R1
set interfaces fe-1/2/0 unit 0 family inet address 10.0.0.1/30 set interfaces fe-1/2/3 unit 0 family inet address 10.0.0.14/30 set interfaces lo0 unit 0 family inet address 192.168.0.1/32 primary set routing-options static route 172.16.1.0/24 next-hop 10.0.0.2 set routing-options static route 172.16.1.0/24 community 64510:1 set routing-options static route 172.16.1.0/24 community large:64510:100:1 set routing-options static route 172.16.2.0/24 next-hop 10.0.0.2 set routing-options static route 172.16.2.0/24 community 64510:2 set routing-options static route 172.16.2.0/24 community large:64510:200:2 set routing-options static route 172.16.3.0/24 next-hop 10.0.0.2 set routing-options static route 172.16.3.0/24 community 64510:3 set routing-options static route 172.16.4.0/24 next-hop 10.0.0.2 set routing-options static route 172.16.4.0/24 community 64510:4 set routing-options router-id 192.168.0.1 set routing-options autonomous-system 64510 set protocols bgp group ext type external set protocols bgp group ext export send-static set protocols bgp group ext peer-as 64511 set protocols bgp group ext neighbor 10.0.0.13 set protocols ospf area 0.0.0.0 interface lo0.0 passive set protocols ospf area 0.0.0.0 interface fe-1/2/0.0 set policy-options policy-statement send-static term 1 from protocol static set policy-options policy-statement send-static term 1 then accept
设备 R2
set interfaces fe-1/2/0 unit 0 family inet address 10.0.0.2/30 set interfaces lo0 unit 0 family inet address 192.168.0.2/32 set interfaces lo0 unit 0 family inet address 172.16.1.1/32 set interfaces lo0 unit 0 family inet address 172.16.2.2/32 set interfaces lo0 unit 0 family inet address 172.16.3.3/32 set interfaces lo0 unit 0 family inet address 172.16.4.4/32 set routing-options router-id 192.168.0.2 set protocols ospf area 0.0.0.0 interface lo0.0 passive set protocols ospf area 0.0.0.0 interface fe-1/2/0.0
设备 R3
set interfaces fe-1/2/3 unit 0 family inet address 10.0.0.13/30 set interfaces lo0 unit 0 family inet address 192.168.0.3/32 set routing-options router-id 192.168.0.3 set routing-options autonomous-system 64511 set protocols bgp group to-R1 type external set protocols bgp group to-R1 import set-large-comms set protocols bgp group to-R1 peer-as 64510 set protocols bgp group to-R1 neighbor 10.0.0.14 set policy-options policy-statement set-large-comms term route-1 from route-filter 172.16.1.0/24 exact set policy-options policy-statement set-large-comms term route-1 then community add large2-as set policy-options policy-statement set-large-comms term route-1 then accept set policy-options policy-statement set-large-comms term route-2 from route-filter 172.16.2.0/24 exact set policy-options policy-statement set-large-comms term route-2 then community add large2-ip set policy-options policy-statement set-large-comms term route-2 then accept set policy-options policy-statement set-large-comms term route-3 from route-filter 172.16.3.0/24 exact set policy-options policy-statement set-large-comms term route-3 then community add large1-as set policy-options policy-statement set-large-comms term route-3 then accept set policy-options policy-statement set-large-comms term route-4 from route-filter 172.16.4.0/24 exact set policy-options policy-statement set-large-comms term route-4 then community add large1-ip set policy-options policy-statement set-large-comms term route-4 then accept set policy-options community large1-as members large:64511:3:1 set policy-options community large1-ip members large:7777:4:1 set policy-options community large2-as members large:64511:1:1 set policy-options community large2-ip members large:7777:2:1
程序
分步过程
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 CLI 的信息，请参阅 在配置模式下使用 CLI 编辑器Junos OS CLI 用户指南。
要配置设备 R3：
配置接口。
[edit interfaces] set fe-1/2/3 unit 0 family inet address 10.0.0.13/30 set lo0 unit 0 family inet address 192.168.0.3/32
配置自治系统 (AS) 编号和路由器 ID。
[edit routing-options] set router-id 192.168.0.3 set autonomous-system 64511
配置与设备 R1 的 EBGP 连接。
[edit protocols bgp group to-R1] set type external set import set-large-comms set peer-as 64510 set neighbor 10.0.0.14
配置将大型社区值添加到从设备 R1 接收的路由的策略。
大型社区使用 ：
global administrator:assigned number:assigned number的large表示法。特定社区值可以是在特定参数内实现管理目标的任何值。[edit policy-options policy-statement set-large-comms] set term route-1 from route-filter 172.16.1.0/24 exact set term route-1 then community add large2-as set term route-1 then accept set term route-2 from route-filter 172.16.2.0/24 exact set term route-2 then community add large2-ip set term route-2 then accept set term route-3 from route-filter 172.16.3.0/24 exact set term route-3 then community add large1-as set term route-3 then accept set term route-4 from route-filter 172.16.4.0/24 exact set term route-4 then community add large1-ip set term route-4 then accept
[edit policy-options ] set community large1-as members large:64511:3:1 set community large1-ip members large:7777:4:1 set community large2-as members large:64511:1:1 set community large2-ip members large:7777:2:1
结果
在配置模式下，输入 show interfaces 、show protocols、show policy-options 和 show routing-options 命令，以确认您的配置。如果输出未显示预期的配置，请重复此示例中的说明，以便进行更正。
user@R3# show interfaces
fe-1/2/3 {
unit 0 {
family inet {
address 10.0.0.13/30;
}
}
}
lo0 {
unit 0 {
family inet {
address 192.168.0.3/32;
}
}
}
user@R3# show protocols
bgp {
group to-R1 {
type external;
import set-large-comms;
peer-as 64510;
neighbor 10.0.0.14;
}
}
user@R3# show policy-options
policy-statement set-large-comms {
term route-1 {
from {
route-filter 172.16.1.0/24 exact;
}
then {
community add large2-as;
accept;
}
}
term route-2 {
from {
route-filter 172.16.2.0/24 exact;
}
then {
community add large2-ip;
accept;
}
}
term route-3 {
from {
route-filter 172.16.3.0/24 exact;
}
then {
community add large1-as;
accept;
}
}
term route-4 {
from {
route-filter 172.16.4.0/24 exact;
}
then {
community add large1-ip;
accept;
}
}
}
community large1-as members large:64511:3:1;
community large1-ip members large:7777:4:1;
community large2-as members large:64511:1:1;
community large2-ip members large:7777:2:1;
user@R3# show routing-options router-id 192.168.0.3; autonomous-system 64511;
如果完成设备配置，请从配置模式输入 commit。
验证
确认配置工作正常。
验证 R1
目的
在设备 R1 上，检查 172.16。路由表中的路由。
操作
user@R1> show route protocol static match-prefix 172.16.* detail
inet.0: 17 destinations, 17 routes (17 active, 0 holddown, 0 hidden)
172.16.1.0/24 (1 entry, 1 announced)
*Static Preference: 5
Next hop type: Router, Next hop index: 580
Address: 0xb7a1270
Next-hop reference count: 9
Next hop: 10.0.0.2 via fe-1/2/0.0, selected
Session Id: 0x140
State: < Active Int Ext >
Local AS: 64510
Age: 4d 19:02:23
Validation State: unverified
Task: RT
Announcement bits (2): 0-KRT 4-BGP_RT_Background
AS path: I
Communities: 64510:1 large:64510:100:1
172.16.2.0/24 (1 entry, 1 announced)
*Static Preference: 5
Next hop type: Router, Next hop index: 580
Address: 0xb7a1270
Next-hop reference count: 9
Next hop: 10.0.0.2 via fe-1/2/0.0.0, selected
Session Id: 0x140
State: < Active Int Ext >
Local AS: 64510
Age: 4d 19:02:23
Validation State: unverified
Task: RT
Announcement bits (2): 0-KRT 4-BGP_RT_Background
AS path: I
Communities: 64510:2 large:64510:200:2
172.16.3.0/24 (1 entry, 1 announced)
*Static Preference: 5
Next hop type: Router, Next hop index: 580
Address: 0xb7a1270
Next-hop reference count: 9
Next hop: 10.0.0.2 via fe-1/2/0.0.0, selected
Session Id: 0x140
State: < Active Int Ext >
Local AS: 64510
Age: 4d 22:17:12
Validation State: unverified
Task: RT
Announcement bits (2): 0-KRT 4-BGP_RT_Background
AS path: I
Communities: 64510:3
172.16.4.0/24 (1 entry, 1 announced)
*Static Preference: 5
Next hop type: Router, Next hop index: 580
Address: 0xb7a1270
Next-hop reference count: 9
Next hop: 10.0.0.2 via fe-1/2/0.0.0, selected
Session Id: 0x140
State: < Active Int Ext >
Local AS: 64510
Age: 4d 22:17:12
Validation State: unverified
Task: RT
Announcement bits (2): 0-KRT 4-BGP_RT_Background
AS path: I
Communities: 64510:4
. . .
意义
输出显示常规社区和大型社区值附加到路由。
注：
社区附加到静态路由，从而证明常规社区和大型社区都可以附加到静态路由。
验证 R3
目的
在设备 R3 上，检查 172.16。路由表中的路由。
操作
user@R3> show route protocol bgp match-prefix 172.16.* detail
inet.0: 14 destinations, 14 routes (14 active, 0 holddown, 0 hidden)
172.16.1.0/24 (1 entry, 1 announced)
*BGP Preference: 170/-101
Next hop type: Router, Next hop index: 581
Address: 0xb7a10f0
Next-hop reference count: 8
Source: 10.0.0.14
Next hop: 10.0.0.14 via fe-1/2/3.0, selected
Session Id: 0x140
State: < Active Ext >
Local AS: 64511 Peer AS: 64510
Age: 3d 16:36:18
Validation State: unverified
Task: BGP_64510.10.0.0.14
Announcement bits (1): 0-KRT
AS path: 64510 I
Communities: 64510:1 large:64510:100:1 large:64511:1:1
Accepted
Localpref: 100
Router ID: 192.168.0.1
172.16.2.0/24 (1 entry, 1 announced)
*BGP Preference: 170/-101
Next hop type: Router, Next hop index: 581
Address: 0xb7a10f0
Next-hop reference count: 8
Source: 10.0.0.14
Next hop: 10.0.0.14 via fe-1/2/3.0, selected
Session Id: 0x140
State: < Active Ext >
Local AS: 64511 Peer AS: 64510
Age: 3d 16:36:18
Validation State: unverified
Task: BGP_64510.10.0.0.14
Announcement bits (1): 0-KRT
AS path: 64510 I
Communities: 64510:2 large:7777:2:1 large:64510:200:2
Accepted
Localpref: 100
Router ID: 192.168.0.1
172.16.3.0/24 (1 entry, 1 announced)
*BGP Preference: 170/-101
Next hop type: Router, Next hop index: 581
Address: 0xb7a10f0
Next-hop reference count: 8
Source: 10.0.0.14
Next hop: 10.0.0.14 via fe-1/2/3.0, selected
Session Id: 0x140
State: < Active Ext >
Local AS: 64511 Peer AS: 64510
Age: 3d 16:36:18
Validation State: unverified
Task: BGP_64510.10.0.0.14
Announcement bits (1): 0-KRT
AS path: 64510 I
Communities: 64510:3 large:64511:3:1
Accepted
Localpref: 100
Router ID: 192.168.0.1
172.16.4.0/24 (1 entry, 1 announced)
*BGP Preference: 170/-101
Next hop type: Router, Next hop index: 581
Address: 0xb7a10f0
Next-hop reference count: 8
Source: 10.0.0.14
Next hop: 10.0.0.14 via fe-1/2/3.0, selected
Session Id: 0x140
State: < Active Ext >
Local AS: 64511 Peer AS: 64510
Age: 3d 16:36:18
Validation State: unverified
Task: BGP_64510.10.0.0.14
Announcement bits (1): 0-KRT
AS path: 64510 I
Communities: 64510:4 large:7777:4:1
Accepted
Localpref: 100
Router ID: 192.168.0.1
. . .
意义
输出显示，播发的常规和大型社区值仍然附加到路由上，并且在 R3 收到时添加了新的大型社区值。