ipsec也是可以的

1.2  配置需求及实现的效果

将防火墙部署在互联网出口用于L2TP VPN网关，目前需要安卓（Android）\苹果（IOS）手机使用系统自带的L2TP客户端连接VPN访问内网资源。

【小知识】由于安全性考虑，Android 4.0以后的版本和IOS系统L2TP登录方式全部改为L2TP OVER IPSEC方式，所以防火墙只配置L2TP VPN手机终端无法拨入，需要在防火墙增加IPSEC的配置。

2 组网图

注：防火墙外网接口地址为10.0.0.1。

3 配置步骤

3.1  防火墙上网配置

略（请参考防火墙上网配置案例进行配置）

3.2  L2TP VPN配置

3.2.1  启用L2TP VPN

进入系统视图后开启L2TP功能

system-view

[H3C]l2tp enable

3.2.2  配置地址池用于向L2TP用户下发地址

创建L2TP地址池用于向L2TP用户下发地址，需要注意L2TP下发网段不能与内网网段冲突。

[H3C]ip pool 1 172.16.1.2 172.16.1.254

3.2.3  配置虚模板

在虚模板下绑定全局下创建的L2TP地址池，服务模板下的ip address为L2TP VPN用户的网关，需要和地址池内地址在同一网段。

[H3C]interface Virtual-Template 1

[H3C-Virtual-Template1]ppp authentication-mode chap pap

[H3C-Virtual-Template1]remote address pool 1

[H3C-Virtual-Template1]ip address 172.16.1.1 24

[H3C-Virtual-Template1]quit

3.2.4  创建L2TP用户组

创建L2TP组绑定虚模板

[H3C]l2tp-group 1 mode lns

[H3C-l2tp1]undo tunnel authentication

[H3C-l2tp1]allow l2tp virtual-template 1

[H3C-l2tp1]quit

3.2.5  创建用户

创建的L2TP账号为z，密码为z。

[H3C]local-user z class network

[H3C-luser-network-z]service-type ppp

[H3C-luser-network-z]password simple z

[H3C-luser-network-z]quit

3.2.6  将Virtual-Template接口加入到安全域并放通安全策略

将Virtual-Template 1接口加入Trust区域，如果内网接口也在Trust区域需要放通同域间的安全策略。

[H3C]security-zone name Trust

[H3C-security-zone-Trust]import interface Virtual-Template 1

[H3C-security-zone-Trust]quit

[H3C]security-zone intra-zone default permit

3.3  IPSEC VPN配置

3.3.1  配置共享秘钥

配置共享秘钥为123

[H3C]ike keychain 1

[H3C-ike-keychain-1]pre-shared-key address 0.0.0.0 0 key simple 123

[H3C-ike-keychain-1]quit

3.3.2  配置IKE安全提议

配置多个安全提议用于匹配不同的终端认证\加密算法。

[H3C]ike proposal 1

[H3C-ike-proposal-1]encryption-algorithm aes-cbc-128

[H3C-ike-proposal-1]dh group2

[H3C-ike-proposal-1]authentication-algorithm md5

[H3C-ike-proposal-1]quit

[H3C]ike proposal 2

[H3C-ike-proposal-2]encryption-algorithm 3des-cbc

[H3C-ike-proposal-2]dh group2

[H3C-ike-proposal-2]authentication-algorithm md5

[H3C-ike-proposal-2]quit

[H3C]ike proposal 3

[H3C-ike-proposal-3]encryption-algorithm 3des-cbc

[H3C-ike-proposal-3]dh group2

[H3C-ike-proposal-3]authentication-algorithm sha

[H3C-ike-proposal-3]quit

[H3C]ike proposal 4

[H3C-ike-proposal-4]encryption-algorithm aes-cbc-256

[H3C-ike-proposal-4]dh group2

[H3C-ike-proposal-4]authentication-algorithm sha

[H3C-ike-proposal-4]quit

[H3C]ike proposal 5

[H3C-ike-proposal-5]encryption-algorithm DES-CBC

[H3C-ike-proposal-5]dh group2

[H3C-ike-proposal-5]authentication-algorithm sha

[H3C-ike-proposal-5]quit

[H3C]ike proposal 6

[H3C-ike-proposal-6]encryption-algorithm aes-cbc-192

[H3C-ike-proposal-6]dh group2

[H3C-ike-proposal-6]authentication-algorithm sha

[H3C-ike-proposal-6]quit

3.3.3  配置IKE安全框架

配置IKE安全框架调用创建的6个安全提议。

[H3C]ike profile 1

[H3C-ike-profile-1]keychain 1

[H3C-ike-profile-1]match remote identity address 0.0.0.0 0

[H3C-ike-profile-1]proposal 1 2 3 4 5 6

[H3C-ike-profile-1]quit

3.3.4  配置IPSEC安全提议

[H3C]ipsec transform-set 1

[H3C-ipsec-transform-set-1]encapsulation-mode transport

[H3C-ipsec-transform-set-1]esp encryption-algorithm 3des-cbc

[H3C-ipsec-transform-set-1]esp authentication-algorithm MD5

[H3C-ipsec-transform-set-1]quit

[H3C]ipsec transform-set 2

[H3C-ipsec-transform-set-2]encapsulation-mode transport

[H3C-ipsec-transform-set-2]esp encryption-algorithm aes-cbc-128

[H3C-ipsec-transform-set-2]esp authentication-algorithm sha1

[H3C-ipsec-transform-set-2]quit

[H3C]ipsec transform-set 3

[H3C-ipsec-transform-set-3]encapsulation-mode transport

[H3C-ipsec-transform-set-3]esp encryption-algorithm aes-cbc-256

[H3C-ipsec-transform-set-3]esp authentication-algorithm sha1

[H3C-ipsec-transform-set-3]quit

[H3C]ipsec transform-set 4

[H3C-ipsec-transform-set-4]encapsulation-mode transport

[H3C-ipsec-transform-set-4]esp encryption-algorithm des-cbc

[H3C-ipsec-transform-set-4]esp authentication-algorithm sha1

[H3C-ipsec-transform-set-4]quit

[H3C]ipsec transform-set 5

[H3C-ipsec-transform-set-5]encapsulation-mode transport

[H3C-ipsec-transform-set-5]esp encryption-algorithm 3des-cbc

[H3C-ipsec-transform-set-5]esp authentication-algorithm sha1

[H3C-ipsec-transform-set-5]quit

[H3C]ipsec transform-set 6

[H3C-ipsec-transform-set-6]encapsulation-mode transport

[H3C-ipsec-transform-set-6]esp encryption-algorithm aes-cbc-192

[H3C-ipsec-transform-set-6]esp authentication-algorithm sha1

[H3C-ipsec-transform-set-6]quit

3.3.5  配置IPSEC模板

配置IPSEC模板并调用之前创建的6个模板

[H3C]ipsec policy-template z 1

[H3C-ipsec-policy-template-z-1]transform-set 1 2 3 4 5 6

[H3C-ipsec-policy-template-z-1]ike-profile 1

[H3C-ipsec-policy-template-z-1]quit

3.3.6  配置IPSEC策略

[H3C]ipsec policy a 10 isakmp template z

3.3.7  将IPSEC策略在外网接口调用

[H3C]interface GigabitEthernet 2/0/1

[H3C-GigabitEthernet2/0/1]ipsec apply policy a

[H3C-GigabitEthernet2/0/1]quit

3.3.8  外网接口NAT中添加ACL拒绝掉L2TP数据流量做地址转换。

因为在防火墙处理流程上是先进行NAT后进行IPSEC VPN，如果出接口不拒绝掉L2TP数据流会导致回包无法匹配IPSEC兴趣流。

[H3C]acl advanced 3000

[H3C-acl-ipv4-adv-3000]rule deny udp destination-port 1701

[H3C-acl-ipv4-adv-3000]rule permit ip source any

[H3C-acl-ipv4-adv-3000]quit

[H3C]interface GigabitEthernet 2/0/1

[H3C-GigabitEthernet2/0/1]nat outbound 3000

[H3C-GigabitEthernet2/0/1]quit

3.4  保存配置

[H3C]quit

save force

3.5  实验验证

3.5.1  使用安卓手机拨入VPN