squid forward agent

Principle: a machine that can't access the Internet can access the website that can't be accessed through the agent
Here I use my real machine as an agent. The virtual machine accesses the website through the agent
Operating System: Red Hat Enterprise Linux Server 7.2 (Maipo)

squid installation and configuration changes

Real machine (Internet accessible) IP: 172.25.254.56

 [root@dream software]# yum install -y squid                     ###Download squid
 [root@dream software]# vim /etc/squid/squid.conf
  55 # And finally deny all other access to this proxy
  56 http_access allow all                                       ###Allow everyone to connect
  57 
  58 # Squid normally listens to port 3128
  59 http_port 3128
  60 
  61 # Uncomment and adjust the following to add a disk cache directory.
  62 cache_dir ufs /var/spool/squid 100 16 256                   ###100M, 16 first level directories and 256 second level directories in / var/spool/squid
  [root@dream squid]# systemctl start squid
  [root@dream 00]# systemctl stop firewalld

If the firewall is not off: open port 3128 access

Browser in virtual machine:

IP:172.25.254.156

test

The host of the browser ping www.baidu.com is not available, but the browser can access the Internet

squid reverse proxy

Here I use two virtual machines, one IP: 172.25.254.156 and one IP: 172.25.254.102

IP:172.25.254.102

Note: the httpd service of this virtual machine will be shut down

 [root@server ~]# yum install -y squid
 [root@server ~]# vim /etc/squid/squid.conf                            ###You can view help at / usr/share/doc/squid-3.3.8/squid.conf.documented
  55 # And finally deny all other access to this proxy
  56 http_access allow all
  57 
  58 # Squid normally listens to port 3128
  59 http_port 80 vhost vport                                          ###Access through port 80, virtual user, virtual port                               
  60 cache_peer 172.25.254.156 parent 80 0 no-query                    ###Visit 172.25.254.156 through 80, 0 has no backup, no query: tell the server there is no backup
  61
  62 # Uncomment and adjust the following to add a disk cache directory.
  63 cache_dir ufs /var/spool/squid 100 16 256
 [root@server ~]# systemctl start squid
 [root@server ~]# systemctl stop firewalld.service

IP:172.25.254.156

 [root@mysql ~]# vim /var/www/html/index.html
 <h1>172.25.254.156</h1>
 [root@mysql ~]# systemctl start httpd