1.查看装没装拨号软件： 

[root@www root]# rpm -qa|grep pppoe

没有则去yum安装。

 2.查看adsl-setup命令在哪： 
[root@www root]#whereis pppoe

3.设置拨号： 
[root@www root]# /sbin/pppoe-setup 

Enter your Login Name (default root): （这里填宽带连接的用户名） 

接着，要求我们选择使用的网络接口。我们这时候，填入我们刚刚设置的那个网卡。对于大多数只有一个网卡的朋友而言，默认eth0就可以了。 

INTERFACE  

Enter the Ethernet interface connected to the ADSL modem  For Solaris, this is likely to be something like /dev/hme0.  For Linux, it will be ethX, where 'X' is a number.  (default eth0): （eth0） 

接下来，询问的是，adsl连接以后，是否持续保持连接。或者是自动的断开，在指定的时间（以秒数计算）内。多数情况下，我们希望手动的打开关闭连接。所以这里选择默认的no。  
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) 

再下来，就是dns了。我发现很多时候，pppoe都不能够正确获取dns信息。我建议你输入dns地址。这些信息在isp的网站上一般都有公布。  DNS  
Please enter the IP address of your ISP's primary DNS server.  
If your ISP claims that 'the server will provide dynamic 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. (server) 

帐号密码是必须，输入两次。密码显示风格和其他的地方一样，不显示在屏幕上。 
PASSWORD  
Please enter your Password: (宽带连接密码)

 Please re-enter your Password:  

下面的设置，是表示是否允许普通用户启用/关闭 ADSL连接。默认是允许。  
Please enter 'yes' (two letters, lower-case.) if you want to allow  normal user to start or stop DSL connection (default yes): (yes) 

我们看下防火墙选项。这里提供的防火墙可以给你提供基本的安全保护。我不推荐你使用——你最好选择“NONE”选项。无论是什么样的用户使用，我都建议你使用额外的工具来配置防火墙规则（iptables目前看来是一个非常不错的工具）。  

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)

是否在开机时，打开这个连接？  

 Start this connection at boot time 
Do you want to start this connection at boot time?** (yes) 

所有的配置信息填写完成之后，系统将给出一个报告，完整的显示出你输入的配置信息。如果，你确信你输入的配置信息是正确的，输入yes写入配置文件。输入no放弃配置。 

** Summary of what you entered **

Ethernet Interface: eth0
User name: xy170638010214
Activate-on-demand: No
DNS addresses: Supplied by ISP's server
Firewalling: NONE
User Control: yes
Accept these settings and adjust configuration files (y/n)? (y)

Adjusting /etc/sysconfig/network-scripts/ifcfg-ppp0
Adjusting /etc/ppp/chap-secrets and /etc/ppp/pap-secrets
(But first backing it up to /etc/ppp/chap-secrets.bak)
(But first backing it up to /etc/ppp/pap-secrets.bak)


Congratulations, it should be all set up!
 

Type '/sbin/ifup ppp0' to bring up your xDSL link and '/sbin/ifdown ppp0'to bring it down.
Type '/sbin/pppoe-status /etc/sysconfig/network-scripts/ifcfg-ppp0'to see the link status  

测试拨号  
现在，我们需要测试下我们的拨号是否配置正确了。  
输入adsl-start拨号。一般情况下，我会ping 我的ISP的主WWW服务器。
如果不怕麻烦，打开浏览器测试下，也可以。如果一切ok。那么我们就可以结束我们的配置了。  
当然，你关闭连接的话，使用命令adsl-stop就可以了。

也可以用'/sbin/ifup ppp0'打开。