组网需求

如图1所示：

• PE1和ASBR1属于AS 100，PE2和ASBR2属于AS 200，要求AS 100和AS 200内通过IS-IS协议达到IPv6网络互连的目的。
• PE1和ASBR1的IS-IS进程是1，都是Level-1设备；PE2和ASBR2的IS-IS进程是10，都是Level-1设备。

要求在PE1和PE2之间建立双向跨域SRv6 BE路径，承载L3VPNv4业务。

图1 配置跨域L3VPNv4 over SRv6 BE组网图

配置思路

1. 使能PE和ASBR各接口的IPv6转发能力，配置各接口的IPv6地址。
2. 在PE和ASBR上使能IS-IS，配置Level级别，指定网络实体。
3. 在PE1和PE2上配置VPN实例。
4. 在PE和CE之间建立EBGP对等体关系。
5. 在PE和ASBR上配置IS-IS的SRv6能力。
6. 在ASBR上配置Locator路由相互引入。
7. 在PE之间建立MP-EBGP对等体关系。
8. 在PE上配置利用对等体关系相互发送携带SID的BGP VPNv4路由。
9. 在PE1和PE2上配置SRv6转发功能。

操作步骤

1.使能各接口的IPv6转发能力，配置IPv6地址，以PE1为例，其他路由器的配置过程相同，不再赘述

<HUAWEI> system-view
[~HUAWEI] sysname PE1
[*HUAWEI] commit
[~PE1] interface gigabitethernet 1/0/0
[~PE1-GigabitEthernet1/0/0] ipv6 enable
[*PE1-GigabitEthernet1/0/0] ipv6 address 2001::1 96
[*PE1-GigabitEthernet1/0/0] quit
[*PE1] interface loopback1
[*PE1-LoopBack1] ipv6 enable
[*PE1-LoopBack1] ipv6 address 1::1 128
[*PE1-LoopBack1] commit
[~PE1-LoopBack1] quit

2.配置IS-IS

# 配置PE1。

[~PE1] isis 1
[*PE1-isis-1] is-level level-1
[*PE1-isis-1] cost-style wide
[*PE1-isis-1] network-entity 10.0000.0000.0001.00
[*PE1-isis-1] ipv6 enable topology ipv6
[*PE1-isis-1] quit
[*PE1] interface gigabitethernet 1/0/0
[*PE1-GigabitEthernet1/0/0] isis ipv6 enable 1
[*PE1-GigabitEthernet1/0/0] quit
[*PE1] interface loopback1
[*PE1-LoopBack1] isis ipv6 enable 1
[*PE1-LoopBack1] commit
[~PE1-LoopBack1] quit

# 配置ASBR1。

[~ASBR1] isis 1 
[*ASBR1-isis-1] is-level level-1
[*ASBR1-isis-1] cost-style wide
[*ASBR1-isis-1] network-entity 10.0000.0000.0002.00
[*ASBR1-isis-1] ipv6 enable topology ipv6
[*ASBR1-isis-1] quit
[*ASBR1] interface gigabitethernet 1/0/0
[*ASBR1-GigabitEthernet1/0/0] isis ipv6 enable 1
[*ASBR1-GigabitEthernet1/0/0] quit
[*ASBR1] interface loopback1
[*ASBR1-LoopBack1] isis ipv6 enable 1
[*ASBR1-LoopBack1] commit
[~ASBR1-LoopBack1] quit

# 配置ASBR2。

[~ASBR2] isis 10 
[*ASBR2-isis-10] is-level level-1
[*ASBR2-isis-10] cost-style wide
[*ASBR2-isis-10] network-entity 10.0000.0000.0003.00
[*ASBR2-isis-10] ipv6 enable topology ipv6
[*ASBR2-isis-10] quit
[*ASBR2] interface gigabitethernet 1/0/0
[*ASBR2-GigabitEthernet1/0/0] isis ipv6 enable 10
[*ASBR2-GigabitEthernet1/0/0] quit
[*ASBR2] interface loopback1
[*ASBR2-LoopBack1] isis ipv6 enable 10
[*ASBR2-LoopBack1] commit
[~ASBR2-LoopBack1] quit

# 配置PE2。

[~PE2] isis 10
[*PE2-isis-10] is-level level-1
[*PE2-isis-10] cost-style wide
[*PE2-isis-10] network-entity 10.0000.0000.0004.00
[*PE2-isis-10] ipv6 enable topology ipv6
[*PE2-isis-10] quit
[*PE2] interface gigabitethernet 1/0/0
[*PE2-GigabitEthernet1/0/0] isis ipv6 enable 10
[*PE2-GigabitEthernet1/0/0] quit
[*PE2] interface loopback1
[*PE2-LoopBack1] isis ipv6 enable 10
[*PE2-LoopBack1] commit
[~PE2-LoopBack1] quit

配置完成后，可按如下指导检查IS-IS是否配置成功。

# 显示IS-IS邻居信息。以PE1为例。

[~PE1] display isis peer

                          Peer information for ISIS(1)
                         
  System Id     Interface          Circuit Id        State HoldTime Type     PRI
--------------------------------------------------------------------------------
0000.0000.0002* GE1/0/0            0000.0000.0002.01  Up   8s       L1       64 

Total Peer(s): 1

3.在PE设备上配置使能IPv4地址族的VPN实例，将CE接入PE

# 配置PE1。

[~PE1] ip vpn-instance vpna
[*PE1-vpn-instance-vpna] ipv4-family
[*PE1-vpn-instance-vpna-af-ipv4] route-distinguisher 100:1
[*PE1-vpn-instance-vpna-af-ipv4] vpn-target 111:1 both
[*PE1-vpn-instance-vpna-af-ipv4] quit
[*PE1-vpn-instance-vpna] quit
[*PE1] interface gigabitethernet 2/0/0
[*PE1-GigabitEthernet2/0/0] ip binding vpn-instance vpna
[*PE1-GigabitEthernet2/0/0] ip address 10.1.1.1 24
[*PE1-GigabitEthernet2/0/0] quit
[*PE1] commit

# 配置PE2。

[~PE2] ip vpn-instance vpna
[*PE2-vpn-instance-vpna] ipv4-family
[*PE2-vpn-instance-vpna-af-ipv4] route-distinguisher 200:1
[*PE2-vpn-instance-vpna-af-ipv4] vpn-target 111:1 both
[*PE2-vpn-instance-vpna-af-ipv4] quit
[*PE2-vpn-instance-vpna] quit
[*PE2] interface gigabitethernet 2/0/0
[*PE2-GigabitEthernet2/0/0] ip binding vpn-instance vpna
[*PE2-GigabitEthernet2/0/0] ip address 10.2.1.1 24
[*PE2-GigabitEthernet2/0/0] quit
[*PE2] commit

# 按图1配置各CE的接口IP地址，配置过程请参见后面的配置文件。

配置完成后，在PE设备上执行display ip vpn-instance verbose命令可以看到VPN实例的配置情况。各PE能ping通自己接入的CE。

4.在PE与CE之间建立EBGP对等体关系

# 配置CE1。

[~CE1] interface loopback 1
[*CE1-LoopBack1] ip address 11.11.11.11 32
[*CE1-LoopBack1] quit
[*CE1] bgp 65410
[*CE1-bgp] peer 10.1.1.1 as-number 100
[*CE1-bgp] network 11.11.11.11 32
[*CE1-bgp] quit
[*CE1] commit

# 配置PE1。

[~PE1] bgp 100
[*PE1-bgp] router-id 1.1.1.1
[*PE1-bgp] ipv4-family vpn-instance vpna
[*PE1-bgp-vpna] peer 10.1.1.2 as-number 65410
[*PE1-bgp-vpna] import-route direct
[*PE1-bgp-vpna] commit
[~PE1-bgp-vpna] quit
[~PE1-bgp] quit

# 配置CE2。

[~CE2] interface loopback 1
[*CE2-LoopBack1] ip address 22.22.22.22 32
[*CE2-LoopBack1] quit
[*CE2] bgp 65420
[*CE2-bgp] peer 10.2.1.1 as-number 200
[*CE2-bgp] network 22.22.22.22 32
[*CE2-bgp] quit
[*CE2] commit

# 配置PE2。

[~PE2] bgp 200
[*PE2-bgp] router-id 4.4.4.4
[*PE2-bgp] ipv4-family vpn-instance vpna
[*PE2-bgp-vpna] peer 10.2.1.2 as-number 65420
[*PE2-bgp-vpna] import-route direct
[*PE2-bgp-vpna] commit
[~PE2-bgp-vpna] quit
[~PE2-bgp] quit

配置完成后，在PE设备上执行display bgp vpnv4 vpn-instance peer命令，可以看到PE与CE之间的BGP对等体关系已建立，并达到Established状态。

以PE1与CE1的对等体关系为例：

[~PE1] display bgp vpnv4 vpn-instance vpna peer

 BGP local router ID : 1.1.1.1
 Local AS number : 100

 VPN-Instance vpna, Router ID 1.1.1.1:
 Total number of peers : 1            Peers in established state : 1

  Peer            V    AS  MsgRcvd  MsgSent    OutQ  Up/Down    State        PrefRcv
  10.1.1.2        4   65410  11     9          0     00:06:37   Established  1

5.在PE上配置IS-IS发布SRv6 Locator路由

# 配置PE1。

[~PE1] segment-routing ipv6
[*PE1-segment-routing-ipv6] encapsulation source-address 1::1
[*PE1-segment-routing-ipv6] locator as1 ipv6-prefix 10:: 64 static 32
[*PE1-segment-routing-ipv6-locator] quit
[*PE1-segment-routing-ipv6] quit
[*PE1] isis 1
[*PE1-isis-1] segment-routing ipv6 locator as1
[*PE1-isis-1] commit
[~PE1-isis-1] quit

# 配置PE2。

[~PE2] segment-routing ipv6
[*PE2-segment-routing-ipv6] encapsulation source-address 4::4
[*PE2-segment-routing-ipv6] locator as1 ipv6-prefix 40:: 64 static 32
[*PE2-segment-routing-ipv6-locator] quit
[*PE2-segment-routing-ipv6] quit
[*PE2] isis 10
[*PE2-isis-10] segment-routing ipv6 locator as1
[*PE2-isis-10] commit
[~PE2-isis-10] quit

6.配置Locator路由相互引入

在PE1->PE2方向，需要在ASBR1上配置BGP引入IS-IS发布的Locator路由，并且发布给ASBR2，ASBR2上配置IS-IS引入BGP路由，从而把PE1的Locator路由通过IS-IS发布给PE2。PE2->PE1方向与此类似。

# 配置ASBR1。

[~ASBR1] bgp 100 
[*ASBR1-bgp] router-id 2.2.2.2
[*ASBR1-bgp] peer 2020::2 as-number 200
[*ASBR1-bgp] peer 2020::2 ebgp-max-hop 255
[*ASBR1-bgp] ipv6-family unicast
[*ASBR1-bgp-af-ipv6] peer 2020::2 enable 
[*ASBR1-bgp-af-ipv6] network 10:: 64 
[*ASBR1-bgp-af-ipv6] network 1::1 128
[*ASBR1-bgp-af-ipv6] quit 
[*ASBR1-bgp] quit
[*ASBR1] ip ipv6-prefix p1 permit 40:: 64 
[*ASBR1] ip ipv6-prefix p1 permit 4::4 128
[*ASBR1] route-policy rp1 permit node 10                     
[*ASBR1-route-policy] if-match ipv6 address prefix-list p1
[*ASBR1-route-policy] quit 
[*ASBR1] isis 1
[*ASBR1-isis-1] ipv6 import-route bgp route-policy rp1 level-1 
[*ASBR1-isis-1] quit
[*ASBR1] commit

# 配置ASBR2。

[~ASBR2] bgp 200 
[*ASBR2-bgp] router-id 3.3.3.3
[*ASBR2-bgp] peer 2020::1 as-number 100
[*ASBR2-bgp] peer 2020::1 ebgp-max-hop 255
[*ASBR2-bgp] ipv6-family unicast
[*ASBR2-bgp-af-ipv6] peer 2020::1 enable
[*ASBR2-bgp-af-ipv6] network 40:: 64 
[*ASBR2-bgp-af-ipv6] network 4::4 128 
[*ASBR2-bgp-af-ipv6] quit 
[*ASBR2-bgp] quit
[*ASBR2] ip ipv6-prefix p1 permit 10:: 64 
[*ASBR2] ip ipv6-prefix p1 permit 1::1 128 
[*ASBR2] route-policy rp1 permit node 10                                                
[*ASBR2-route-policy] if-match ipv6 address prefix-list p1                              
[*ASBR2-route-policy] quit 
[*ASBR2] isis 10
[*ASBR2-isis-10] ipv6 import-route bgp route-policy rp1 level-1
[*ASBR2-isis-10] quit
[*ASBR2] commit

7.在PE之间建立MP-EBGP对等体关系，并且配置利用对等体关系相互发送携带SID的BGP VPNv4路由，然后使能SRv6 BE转发功能

# 配置PE1。

[~PE1] bgp 100
[~PE1-bgp] peer 4::4 as-number 200
[*PE1-bgp] peer 4::4 ebgp-max-hop 255
[*PE1-bgp] peer 4::4 connect-interface loopback 1
[*PE1-bgp] ipv4-family vpnv4
[*PE1-bgp-af-vpnv4] peer 4::4 enable
[*PE1-bgp-af-vpnv4] peer 4::4 prefix-sid
[*PE1-bgp-af-vpnv4] quit
[*PE1-bgp] ipv4-family vpn-instance vpna
[*PE1-bgp-vpna] segment-routing ipv6 best-effort
[*PE1-bgp-vpna] segment-routing ipv6 locator as1
[*PE1-bgp-vpna] commit
[~PE1-bgp-vpna] quit
[~PE1-bgp] quit

# 配置PE2。

[~PE2] bgp 200
[~PE2-bgp] peer 1::1 as-number 100
[*PE2-bgp] peer 1::1 ebgp-max-hop 255
[*PE2-bgp] peer 1::1 connect-interface loopback 1
[*PE2-bgp] ipv4-family vpnv4
[*PE2-bgp-af-vpnv4] peer 1::1 enable
[*PE2-bgp-af-vpnv4] peer 1::1 prefix-sid
[*PE2-bgp-af-vpnv4] quit
[*PE2-bgp] ipv4-family vpn-instance vpna
[*PE2-bgp-vpna] segment-routing ipv6 best-effort
[*PE2-bgp-vpna] segment-routing ipv6 locator as1
[*PE2-bgp-vpna] commit
[~PE2-bgp-vpna] quit
[~PE2-bgp] quit

配置完成后，在PE设备上执行display bgp vpnv4 all peer命令，可以看到PE之间的BGP对等体关系已建立，并达到Established状态。以PE1的显示为例：

[~PE1] display bgp vpnv4 all peer

 BGP local router ID : 1.1.1.1 
 Local AS number : 100  
 Total number of peers : 2                 Peers in established state : 2 
  Peer            V          AS  MsgRcvd  MsgSent  OutQ  Up/Down       State  PrefRcv
  4::4            4         200     1512     1520     0 21:55:19 Established        2 

  Peer of IPv4-family for vpn instance :  

  VPN-Instance vpna, Router ID 1.1.1.1:          
  Peer            V          AS  MsgRcvd  MsgSent  OutQ  Up/Down       State  PrefRcv                                               
  10.1.1.2        4       65410     1790     1812     0 0026h03m Established        1 

8.检查配置结果

执行命令display segment-routing ipv6 locator [ locator-name ] verbose查看SRv6的Locator信息。以PE1为例：

[~PE1] display segment-routing ipv6 locator verbose
                        Locator Configuration Table                          
                        ---------------------------                          

LocatorName   : as1                                       LocatorID     : 4  
IPv6Prefix    : 10::                                      PrefixLength  : 64 
Block         : --                                        BlockLength   : 0  
NodeID        : --                                        NodeIdLength  : 0  
ComprStaticLen: 0                                         StaticLength  : 32 
ArgsLength    : 0                                         Reference     : 0  
AutoCSIDPoolID: 0                                         ComprDynLength: 0  
AutoCSIDBegin : --    
AutoCSIDEnd   : --    
StaticCSIDBegin: --   
StaticCSIDEnd : --    
AutoSIDPoolID : 8195                                      DynLength     : 32 
AutoSIDBegin  : 10::1:0:0                                                    
AutoSIDEnd    : 10::FFFF:FFFF:FFFF:FFFF                                      
StaticSIDBegin: 10::1                                                        
StaticSIDEnd  : 10::FFFF:FFFF                                                

Total Locator(s): 1

执行命令display segment-routing ipv6 local-sid end-dt4 forwarding查看SRv6的Local SID表信息。以PE1为例：

[~PE1] display segment-routing ipv6 local-sid end-dt4 forwarding
                    My Local-SID End.DT4 Forwarding Table
                    -------------------------------------                       

SID        : 10::1:0:20/128                               FuncType : End.DT4
VPN Name   : vpna                                         VPN ID   : 3 
LocatorName: as1                                          LocatorID: 1

Total SID(s): 1

同一VPN的CE能够相互Ping通，例如：

[~CE1] ping -a 11.11.11.11 22.22.22.22
  PING 22.22.22.22: 56  data bytes, press CTRL_C to break                      
    Reply from 22.22.22.22: bytes=56 Sequence=1 ttl=253 time=22 ms                        
    Reply from 22.22.22.22: bytes=56 Sequence=2 ttl=253 time=13 ms                     
    Reply from 22.22.22.22: bytes=56 Sequence=3 ttl=253 time=14 ms                
    Reply from 22.22.22.22: bytes=56 Sequence=4 ttl=253 time=15 ms             
    Reply from 22.22.22.22: bytes=56 Sequence=5 ttl=253 time=34 ms             

  --- 22.22.22.22 ping statistics ---                            
    5 packet(s) transmitted    
    5 packet(s) received                            
    0.00% packet loss    
    round-trip min/avg/max = 13/19/34 ms