利用前面所学的知识，进行GRE over IPSec的组网。
一、组网需求
如图所示，RouterA为企业分支网关，RouterB为企业总部网关，分支与总部通过公网建立通信。
企业希望对分支与总部之间相互访问的流量（包括组播数据）进行安全保护。由于组播数据无法直接应用IPSec，所以基于虚拟隧道接口方式建立GRE over IPSec，对Tunnel接口下的流量进行保护。
二、配置思路
采用如下思路配置虚拟隧道接口建立GRE over IPSec：
1）配置物理接口的IP地址和到对端的静态路由，保证两端路由可达；
2）配置GRE Tunnel接口；
3）配置IPSec安全提议，定义IPSec的保护方法；
4）配置IKE对等体，定义对等体间IKE协商时的属性；
5）配置安全框架，并引用安全提议和IKE对等体；
6）在Tunnel接口上应用安全框架，使接口具有IPSec的保护功能；
7）配置Tunnel接口的转发路由，将需要IPSec保护的数据流引到Tunnel接口。
三、操作步骤
1、分别在RouterA和RouterB上配置物理接口的IP地址和到对端的静态路由
# 在RouterA上配置接口的IP地址
<Huawei> system-view
[Huawei] sysname RouterA
[RouterA] interface gigabitethernet 1/0/0
[RouterA-GigabitEthernet1/0/0] ip address 202.138.163.1 255.255.255.0
[RouterA-GigabitEthernet1/0/0] quit
[RouterA] interface gigabitethernet 2/0/0
[RouterA-GigabitEthernet2/0/0] ip address 10.1.1.1 255.255.255.0
[RouterA-GigabitEthernet2/0/0] quit
# 在RouterA上配置到对端的静态路由，此处假设到对端的下一跳地址为202.138.163.2
[RouterA] ip route-static 202.138.162.0 255.255.255.0 202.138.163.2
# 在RouterB上配置接口的IP地址
<Huawei> system-view
[Huawei] sysname RouterB
[RouterB] interface gigabitethernet 1/0/0
[RouterB-GigabitEthernet1/0/0] ip address 202.138.162.1 255.255.255.0
[RouterB-GigabitEthernet1/0/0] quit
[RouterB] interface gigabitethernet 2/0/0
[RouterB-GigabitEthernet2/0/0] ip address 10.1.2.1 255.255.255.0
[RouterB-GigabitEthernet2/0/0] quit
# 在RouterB上配置到对端的静态路由，此处假设到对端下一跳地址为202.138.162.2
[RouterB] ip route-static 202.138.163.0 255.255.255.0 202.138.162.2
2、配置GRE Tunnel接口
# 配置RouterA
[RouterA] interface tunnel 0/0/0
[RouterA-Tunnel0/0/0] ip address 192.168.1.1 255.255.255.0
[RouterA-Tunnel0/0/0] tunnel-protocol gre
[RouterA-Tunnel0/0/0] source 202.138.163.1
[RouterA-Tunnel0/0/0] destination 202.138.162.1
[RouterA-Tunnel0/0/0] quit
# 配置RouterB
[RouterB] interface tunnel 0/0/0
[RouterB-Tunnel0/0/0] ip address 192.168.1.2 255.255.255.0
[RouterB-Tunnel0/0/0] tunnel-protocol gre
[RouterB-Tunnel0/0/0] source 202.138.162.1
[RouterB-Tunnel0/0/0] destination 202.138.163.1
[RouterB-Tunnel0/0/0] quit
3、分别在RouterA和RouterB上创建IPSec安全提议
# 在RouterA上配置IPSec安全提议
[RouterA] ipsec proposal tran1
[RouterA-ipsec-proposal-tran1] esp authentication-algorithm sha2-256
[RouterA-ipsec-proposal-tran1] esp encryption-algorithm aes-128
[RouterA-ipsec-proposal-tran1] quit
# 在RouterB上配置IPSec安全提议
[RouterB] ipsec proposal tran1
[RouterB-ipsec-proposal-tran1] esp authentication-algorithm sha2-256
[RouterB-ipsec-proposal-tran1] esp encryption-algorithm aes-128
[RouterB-ipsec-proposal-tran1] quit
4、分别在RouterA和RouterB上配置IKE对等体
# 在RouterA上配置IKE安全提议。
[RouterA] ike proposal 5
[RouterA-ike-proposal-5] authentication-algorithm sha2-256
[RouterA-ike-proposal-5] encryption-algorithm aes-cbc-128
[RouterA-ike-proposal-5] quit
# 在RouterA上配置IKE对等体
[RouterA] ike peer spub v2
[RouterA-ike-peer-spub] ike-proposal 5
[RouterA-ike-peer-spub] pre-shared-key cipher huawei
[RouterA-ike-peer-spub] quit
# 在RouterB上配置IKE安全提议
[RouterB] ike proposal 5
[RouterB-ike-proposal-5] authentication-algorithm sha2-256
[RouterB-ike-proposal-5] encryption-algorithm aes-cbc-128
[RouterB-ike-proposal-5] quit
# 在RouterB上配置IKE对等体
[RouterB] ike peer spua v2
[RouterB-ike-peer-spua] ike-proposal 5
[RouterB-ike-peer-spua] pre-shared-key cipher huawei
[RouterB-ike-peer-spua] quit
5、分别在RouterA和RouterB上创建安全框架
# 在RouterA上配置安全框架
[RouterA] ipsec profile profile1
[RouterA-ipsec-profile-profile1] proposal tran1
[RouterA-ipsec-profile-profile1] ike-peer spub
[RouterA-ipsec-profile-profile1] quit
# 在RouterB上配置安全框架
[RouterB] ipsec profile profile1
[RouterB-ipsec-profile-profile1] proposal tran1
[RouterB-ipsec-profile-profile1] ike-peer spua
[RouterB-ipsec-profile-profile1] quit
6、分别在RouterA和RouterB的接口上应用各自的安全框架
# 在RouterA的接口上引用安全框架
[RouterA] interface tunnel 0/0/0
[RouterA-Tunnel0/0/0] ipsec profile profile1
[RouterA-Tunnel0/0/0] quit
# 在RouterB的接口上引用安全框架
[RouterB] interface tunnel 0/0/0
[RouterB-Tunnel0/0/0] ipsec profile profile1
[RouterB-Tunnel0/0/0] quit
# 此时在RouterA和RouterB上执行display ipsec profile会显示所配置的信息
7、配置Tunnel接口的转发路由，将需要IPSec保护的数据流引到Tunnel接口
# 在RouterA上配置Tunnel接口的转发路由
[RouterA] ip route-static 10.1.2.0 255.255.255.0 tunnel 0/0/0
# 在RouterB上配置Tunnel接口的转发路由
[RouterB] ip route-static 10.1.1.0 255.255.255.0 tunnel 0/0/0
8、检查配置结果
# 配置成功后，分别在RouterA和RouterB上执行display ike sa v2会显示所配置的信息，以RouterA为例。
[RouterA] display ike sa v2
Conn-ID Peer VPN Flag(s) Phase
---------------------------------------------------------------
22 202.138.162.1 0 RD|ST 2
21 202.138.162.1 0 RD|ST 1
Flag Description:
RD--READY ST--STAYALIVE RL--REPLACED FD--FADING TO--TIMEOUT
# 配置成功后，分别在RouterA和RouterB上执行display ipsec sa会显示所配置的信息，以RouterA为例。
[RouterA] display ipsec sa
===============================
Interface: Tunnel0/0/0
Path MTU: 1500
===============================
-----------------------------
IPSec profile name: "profile1"
Mode : PROF-ISAKMP
-----------------------------
Connection ID : 22
Encapsulation mode: Tunnel
Tunnel local : 202.138.163.1
Tunnel remote : 202.138.162.1
Qos pre-classify : Disable
[Outbound ESP SAs]
SPI: 1599804596 (0x5f5b14b4)
Proposal: ESP-ENCRYPT-AES-128 SHA2-256-128
SA remaining key duration (bytes/sec): 1887436800/2489
Max sent sequence-number: 0
UDP encapsulation used for NAT traversal: N
[Inbound ESP SAs]
SPI: 2169616882 (0x8151b9f2)
Proposal: ESP-ENCRYPT-AES-128 SHA2-256-128
SA remaining key duration (bytes/sec): 1887436800/2489
Max received sequence-number: 0
Anti-replay window size: 32
UDP encapsulation used for NAT traversal: N
四、配置文件
RouterA的配置文件
#
sysname RouterA
#
ipsec proposal tran1
esp authentication-algorithm sha2-256
esp encryption-algorithm aes-128
#
ike proposal 5
encryption-algorithm aes-cbc-128
authentication-algorithm sha2-256
#
ike peer spub v2
pre-shared-key cipher Huawei
ike-proposal 5
#
ipsec profile profile1
ike-peer spub
proposal tran1
#
interface Tunnel0/0/0
ip address 192.168.1.1 255.255.255.0
tunnel-protocol gre
source 202.138.163.1
destination 202.138.162.1
ipsec profile profile1
#
interface GigabitEthernet1/0/0
ip address 202.138.163.1 255.255.255.0
#
interface GigabitEthernet2/0/0
ip address 10.1.1.1 255.255.255.0
#
ip route-static 202.138.162.0 255.255.255.0 202.138.163.2
ip route-static 10.1.2.0 255.255.255.0 tunnel0/0/0
#
return
RouterB的配置文件
#
sysname RouterB
#
ipsec proposal tran1
esp authentication-algorithm sha2-256
esp encryption-algorithm aes-128
#
ike proposal 5
encryption-algorithm aes-cbc-128
authentication-algorithm sha2-256
#
ike peer spua v2
pre-shared-key cipher Huawei
ike-proposal 5
#
ipsec profile profile1
ike-peer spua
proposal tran1
#
interface Tunnel0/0/0
ip address 192.168.1.2 255.255.255.0
tunnel-protocol gre
source 202.138.162.1
destination 202.138.163.1
ipsec profile profile1
#
interface GigabitEthernet1/0/0
ip address 202.138.162.1 255.255.255.0
#
interface GigabitEthernet2/0/0
ip address 10.1.2.1 255.255.255.0
#
ip route-static 202.138.163.0 255.255.255.0 202.138.162.2
ip route-static 10.1.1.0 255.255.255.0 tunnel0/0/0
#
return