How can Centos access the internet when proxy is used in the intranet?

If Centos uses proxy over the intranet, how to access the Internet is required to be developed in Linux. Therefore, I have installed a virtual machine today and a Centos6232-bit system on the virtual machine. After installation, the first problem encountered is that the network cannot be connected. In a Windows environment, how does one access the internet when Centos uses a proxy on the intranet? due to work needs to be developed in Linux, I have installed a virtual machine today, centos 6.2 32-bit system is installed on the virtual machine. After installation, the first problem encountered is that the network cannot be connected. In Windows, the company uses a proxy to connect to the internet. Therefore, I first set the proxy IP address and port number in firefox. After the settings are complete, you can open the webpage. Then I installed the Chinese input method with yum and found an error. The reason is that yum needs to obtain the downloaded package online, and no proxy IP address is set in the system. Therefore, switch to the root user. Do the following: 1. set the environment variable # vi/etc/profile http_proxy = http: // 192.168.20.20 in the profile file: 3128 # specify the proxy server address https_proxy = http: // 192.168.20.20: 3128 ftp_proxy = http: // 192.168.20.20: 3128 no_proxy = 192.168.20. # Do not use a proxy when accessing the LAN address (192.168.20.0/24 CIDR block). you can use commas to separate multiple addresses: export http_proxy https_proxy ftp_proxy no_proxy. save and exit. 2. source/etc/profile takes effect.