一、组网需求
RouterB接收了一个经过EBGP的更新报文并将之传给RouterC。RouterC被配置为路由反射器，它有两个客户：RouterB和RouterD。RouterB和RouterD间不需一个IBGP连接，当RouterC接收了来自RouterB的路由更新时，它将此信息反射给RouterD，反之亦然。

试验设备：RTA（MSR20-21），RTB（MSR20-20）,RTC（MSR30-20）,RTD（MSR30-20）

适用版本：Version 5.20, Beta 1105

二、组网图
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图 1 BGP4+路由反射组网图

三、配置步骤
以下为RouterA配置： #
ipv6
#
interface Ethernet0/1
port link-mode route
ipv6 address 1::1/96
#
interface NULL0
#
interface LoopBack0
ipv6 address 1:1:1::1/128
#
bgp 100
undo synchronization
#
ipv6-family
//发布该网段的路由，此处为loopback0地址
network 1:1:1::1 128
undo synchronization
//与对端建立EBGP连接
peer 1::2 as-number 200 以下为RouterB配置： #
ipv6
#
interface Ethernet0/0
port link-mode route
ipv6 address 2::1/96
#
interface Ethernet0/1
port link-mode route
ipv6 address 1::2/96
#
interface LoopBack0
ipv6 address 2:2:2::2/128
#
bgp 200
undo synchronization
#
ipv6-family
network 2:2:2::2 128
//引入直连路由以保证下一跳路由可达
import-route direct
undo synchronization
//注意：此处并未将Router D加入对等体
peer 1::1 as-number 100
peer 2::2 as-number 200 以下为RouterC配置： #
ipv6
#
interface LoopBack0
ipv6 address 3:3:3::3/128
#
interface GigabitEthernet0/0
port link-mode route
ipv6 address 2::2/96
#
interface GigabitEthernet0/1
port link-mode route
ipv6 address 3::1/96
//BGP部分配置
#
bgp 200
undo synchronization
#
ipv6-family
network 3:3:3::3 128
import-route direct
undo synchronization
group alanker internal
//设定组内的对等体都为反射器的客户端
peer alanker reflect-client
peer 2::1 group alanker
peer 3::2 group alanker 以下为RouterD配置： #
ipv6
#
interface LoopBack0
ipv6 address 4:4:4::4/128
#
interface GigabitEthernet0/0
port link-mode route
ipv6 address 3::2/96
ip address 1.0.0.4 255.255.255.0
#

interface GigabitEthernet0/1
port link-mode route
#
bgp 200
undo synchronization
#
ipv6-family
network 4:4:4::4 128
import-route direct
undo synchronization
peer 3::1 as-number 200
四、配置关键点

1．作为反射client的RouterB、D上无需配reflect-client，这些都是要在反射器routerC上配的。
2．需要在边界路由器RouterB与RouterC上引入直连路由，否则在ping 1:1:1::1地址的时候找不到下一跳1::1, 即无法到达BGP路由表中的下一跳。因为边界路由器在向IBGP发布路由的时候不改变该条路由的下一跳。

五、试验分析
 
1. 在RouterA上再配置一个loopback地址：2001：da8::1, 并在BGP视图下用如下命
令使能：（红色部分）
[RouterA-2021-bgp-af-ipv6]dis th
#
ipv6-family
network 1:1:1::1 128
network 2001:DA8::1 128
undo synchronization
peer 1::2 as-number 200
 
此时在RouterB与RouterD的BGP路由表中均有到达该地址的路由，
<RouterB-2020>display bgp ipv6 routing-table
 
Total Number of Routes: 9
 
BGP Local router ID is 1.0.0.2
Status codes: * - valid, > - best, d - damped,
h - history, i - internal, s - suppressed, S - Stale
Origin : i - IGP, e - EGP, ? - incomplete
 
*> Network : 1:: PrefixLen : 96
NextHop : 1::2 LocPrf :
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: ?
 
*> Network : 1:1:1::1 PrefixLen : 128
NextHop : 1::1 LocPrf :
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: 100 i
 
*> Network : 2:: PrefixLen : 96
NextHop : 2::1 LocPrf :
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: ?
 
* i Network : 2:: PrefixLen : 96
NextHop : 2::2 LocPrf : 100
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: ?
 
*> Network : 2:2:2::2 PrefixLen : 128
NextHop : ::1 LocPrf :
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: i
 
*>i Network : 3:: PrefixLen : 96
NextHop : 2::2 LocPrf : 100
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: ?
 
*>i Network : 3:3:3::3 PrefixLen : 128
NextHop : 2::2 LocPrf : 100
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: i
 
*>i Network : 4:4:4::4 PrefixLen : 128
NextHop : 3::2 LocPrf : 100
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: i
 
*> Network : 2001:DA8::1 PrefixLen : 128
NextHop : 1::1 LocPrf :
PrefVal : 0 Label : NULL
MED : 0
Path/Ogn: 100 i
 
从D上可以ping通该地址，结果如下：
<RouterD-3020>ping ipv6 2001:da8::1
PING 2001:da8::1 : 56 data bytes, press CTRL_C to break
Reply from 2001:DA8::1
bytes=56 Sequence=1 hop limit=62 time = 3 ms
Reply from 2001:DA8::1
bytes=56 Sequence=2 hop limit=62 time = 3 ms
Reply from 2001:DA8::1
bytes=56 Sequence=3 hop limit=62 time = 3 ms
Reply from 2001:DA8::1
bytes=56 Sequence=4 hop limit=62 time = 4 ms
Reply from 2001:DA8::1
bytes=56 Sequence=5 hop limit=62 time = 3 ms
 
--- 2001:da8::1 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 3/3/4 ms