用U盘安装 CentOS 6.4 + Windows 7双系统 （Win 7下安装 CentOs 6.4) （安装见本文下面的连接），但是有了系统怎么可以不联网，太痛苦了！
这一篇是 CentOS 6.4 电信ADSL 拨号连接的配置，亲测
参考：CentOS 6.4 电信宽带链接网络配置
1.下载 rp-pppoe-3.8.tar.gz
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具体下载目录在 /2015年资料/1月/11日/CentOS 6.4 电信ADSL拨号上网网络配置
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2.安装 rp-pppoe（对文件所在文件夹右键在终端打开）
解压 rp-pppoe-3.8.tar.gz ：
#tar -zxf rp-pppoe-3.8.tar.gz
进入生成的目录：
#cd rp-pppoe-3.8
在所在目录内运行脚本 go：
#./go
将自动进行编译和安装
3、网络配置 （红色为输入，蓝色为注释）
[root@Cheng liaojch3]# pppoe-setup (输入 pppoe-setup )
Welcome to the Roaring Penguin PPPoE client setup.
First, I will run some checks on your system to make sure the PPPoE client is installed properly...
Looks good!
Now, please enter some information:
USER NAME
>>> Enter your PPPoE user name (default cz743720): cz743720 （输入上网账号)
INTERFACE
>>> Enter the Ethernet interface connected to the DSL modem
For Solaris, this is likely to be something like /dev/hme0.
For Linux, it will be ethn, where 'n' is a number.
(default eth0): eth0 （选择你的网卡，默认为 eth0）
Do you want the link to come up on demand, or stay up continuously?
If you want it to come up on demand, enter the idle time in seconds after which the link should be dropped.
If you want the link to stay up permanently, enter 'no' (two letters, lower-case.)
NOTE: Demand-activated links do not interact well with dynamic IP
addresses. You may have some problems with demand-activated links.
>>> Enter the demand value (default no): no （这里填 no 或 直接回车）
DNS
Please enter the IP address of your ISP's primary DNS server.
If your ISP claims that 'the server will provide DNS addresses', enter 'server' (all lower-case) here.
If you just press enter, I will assume you know what you are doing and not modify your DNS setup.
>>> Enter the DNS information here: 202.96.128.86 （输入首选 DNS 地址，这个很重要，我一开始看网上是填 sever 表示自动获取DNS，但没有成功， 后来我查了自己所在城市DNS地址，这里是广东“其他地区”的首选DNS，建议百度自己的DNS地址）
Please enter the IP address of your ISP's secondary DNS server.
If you just press enter, I will assume there is only one DNS server.
>>> Enter the secondary DNS server address here: 202.96.128.143 （备用 DNS 地址，同样查一下）
PASSWORD
>>> Please enter your PPPoE password: （输入密码）
>>> Please re-enter your PPPoE password: （再次输入密码）
FIREWALLING
Please choose the firewall rules to use.
Note that these rules are very basic.
You are strongly encouraged to use a more sophisticated firewall setup; however, these will provide basic security.
If you are running any servers on your machine, you must choose 'NONE' and set up firewalling yourself.
Otherwise, the firewall rules will deny access to all standard servers like Web, e-mail, ftp, etc.
If you are using SSH, the rules will block outgoing SSH connections which allocate a privileged source port.
The firewall choices are:
0 - NONE: This script will not set any firewall rules. You are responsible for ensuring the security of your machine.
You are STRONGLY recommended to use some kind of firewall rules.
1 - STANDALONE: Appropriate for a basic stand-alone web-surfing workstation
2 - MASQUERADE: Appropriate for a machine acting as an Internet gateway
for a LAN
>>> Choose a type of firewall (0-2): 0 （选择防火墙，0表示不开启防火墙）
** Summary of what you entered **
Ethernet
Interface: eth0
User name: cz743720
Activate-on-demand: No
Primary DNS:202.96.128.86
Secondary DNS:202.96.128.143
Firewalling:NONE
>>> Accept these settings and adjust configuration files (y/n)? y （填 y 确认）
Adjusting /etc/ppp/pppoe.conf
Adjusting /etc/resolv.conf (But first backing it up to /etc/resolv.conf-bak)
Adjusting /etc/ppp/pap-secrets and /etc/ppp/chap-secrets (But first backing it up to /etc/ppp/pap-secrets-bak) (But first backing it up to /etc/ppp/chap-secrets-bak)
Congratulations, it should be all set up!
Type 'pppoe-start' to bring up your PPPoE link and 'pppoe-stop' to bring
it down. Type 'pppoe-status' to see the link status.
[root@Cheng liaojch3]# pppoe-start （ 用 pppoe-start 进行连接）
. Connected! (连接成功，你可以用 ping 进行测试一下）
4、上网命令（用 root 权限）
拨号上网 pppoe-start
断开上网 pppoe-stop
查看状态 pppoe-status