阿里云centos 7配置网关服务器

柔光的暖阳◎ 2022-12-30 15:51 338阅读 0赞

# 1、准备 #

## 1.1 服务器 ##

两台服务器

*  ECS1（没有外网）：172.16.5.248
 *  ECS2（有外网IP，其实是VPC做了NAT）：172.16.5.245

## 1.2 安装iptables ##

>systemctl stop firewalld #关闭防火墙
    >yum install iptables-services
    >systemctl enable iptables
    >systemctl start iptables

# 2、配置 #

阿里云VPC网关导致不能按照配置普通网关一样配置（参考：[https://www.cnblogs.com/EasonJim/p/10206728.html][https_www.cnblogs.com_EasonJim_p_10206728.html]），必须结合VPC配置0.0.0.0/0来进行下一跳，不然你在ECS怎么设置都无法成功。其实这个问题是由于VPC本身最上层做了NAT，并通过route查看会发现253这个地址有VPC占用，无论怎么配置0.0.0.0的下一跳都会先转到253这个地址。

## 2.1 ECS2配置 ##

公网网络的机器(ECS2)上执行:

#打开端口转发
    >echo “1” > /proc/sys/net/ipv4/ip_forward
    #重新加载配置，使配置生效
    >sysctl -p
    #配置iptables做SNAT，设置转发规则
    >iptables -t nat -I POSTROUTING -s 172.16.5.0/24 -j SNAT --to-source 172.16.5.245
    #保存更改
    >service iptables save
    #重启防火墙
    >service iptables restart

这里需要注意改成自己的IP，将172.16.5.0网段的网络请求转发到172.16.5.245。

## 2.2 配置VPC路由规则 ##

阿里云ECS若要路由成功，还需要配置VPC路由规则，打开阿里云VPC控制台，添加路由表，新增一条0.0.0.0/0(默认路由)的规则

网络与安全->路由表-管理->路由条目列表->添加自定义路由条目

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGluZ3poZTI_size_16_color_FFFFFF_t_70][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGluZ3poZTI_size_16_color_FFFFFF_t_70 1][]

esc示例添加ECS2

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGluZ3poZTI_size_16_color_FFFFFF_t_70 2][]

# 3、测试 #

## 3.1 访问成功 ##

登陆ECS1，访问百度域名

>ping www.baidu.com
    PING www.a.shifen.com (180.101.49.11) 56(84) bytes of data.
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=1 ttl=49 time=11.5 ms
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=2 ttl=49 time=11.6 ms
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=3 ttl=49 time=11.5 ms
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=4 ttl=49 time=11.5 ms
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=5 ttl=49 time=11.5 ms
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=6 ttl=49 time=11.5 ms
    64 bytes from 180.101.49.11 (180.101.49.11): icmp_seq=7 ttl=49 time=11.5 ms

## 3.2 访问失败 ##

>ping www.baidu.com
    PING www.a.shifen.com (180.101.49.12) 56(84) bytes of data.
    From 172.16.5.245 (172.16.5.245) icmp_seq=7 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=8 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=9 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=10 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=11 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=12 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=13 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=14 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=15 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=16 Destination Host Prohibited
    From 172.16.5.245 (172.16.5.245) icmp_seq=17 Destination Host Prohibited

此时将ECS2的防火墙关闭，命令：iptables -F.然后就可以ping通了。

参考文章：

[https://www.cnblogs.com/EasonJim/p/10206743.html][https_www.cnblogs.com_EasonJim_p_10206743.html]

[https://blog.alovn.cn/2020/05/22/aliyun-ecs-connect-network/][https_blog.alovn.cn_2020_05_22_aliyun-ecs-connect-network]

[https://amos-x.com/index.php/amos/archives/centos7-aliyun-nat/][https_amos-x.com_index.php_amos_archives_centos7-aliyun-nat]

[https://blog.csdn.net/weixin\_44549974/article/details/89576122][https_blog.csdn.net_weixin_44549974_article_details_89576122]

[https_www.cnblogs.com_EasonJim_p_10206728.html]: https://www.cnblogs.com/EasonJim/p/10206728.html
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGluZ3poZTI_size_16_color_FFFFFF_t_70]: /images/20221120/9076bd5afcdc4516860e36bc77b10d19.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGluZ3poZTI_size_16_color_FFFFFF_t_70 1]: /images/20221120/b279ce1c35da4f10b5822e1b28f74f2f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGluZ3poZTI_size_16_color_FFFFFF_t_70 2]: /images/20221120/3406843f712b4f4980569249edebcb88.png
[https_www.cnblogs.com_EasonJim_p_10206743.html]: https://www.cnblogs.com/EasonJim/p/10206743.html
[https_blog.alovn.cn_2020_05_22_aliyun-ecs-connect-network]: https://blog.alovn.cn/2020/05/22/aliyun-ecs-connect-network/
[https_amos-x.com_index.php_amos_archives_centos7-aliyun-nat]: https://amos-x.com/index.php/amos/archives/centos7-aliyun-nat/
[https_blog.csdn.net_weixin_44549974_article_details_89576122]: https://blog.csdn.net/weixin_44549974/article/details/89576122