这几天不在学校了，回家得用猫拨号上网了，在win7下面拨号一点问题都没有，在Fedora下，使用拨号上网就不是那么简单了，下面是我在Fedora 14上尝试过的方法（对老版本的fedora也同样奏效），还是比较方便的。Fedora提供了配置工具来设置拨号上网的参数。这里要使用的工具有三个：pppoe-setup, pppoe-connect 和 pppoe-stop.

但在使用这些工具之前，先把自己提升到root权限，用su或者su -命令就可以。

pppoe-setup: 设置拨号参数，使用一次就行了。

pppoe-connect: 在终端里输入用以拨号上网。

pppoe-stop: 很容易理解，这是用来断开链接的。

首先，使自己成为根用户（root用户）。

[cynicholas@cynicholas ~]$ su
Password:

然后运行pppoe-setup命令。

[root@cynicholas]# pppoe-setup

然后你会看到pppoe-setup会输出如下的提示。

Welcome to the PPPoE client setup. First, I will run some checks on
your system to make sure the PPPoE client is installed properly...

现在它提示你输入你在ISP所用的用户名（也叫做帐号,比如我家就是座机号码）。

LOGIN NAME

Enter your Login Name (default work): 051212345678

然后你会看到如下提示，这时他会提示你输入使用连接的以太网接口，不需要输入任何内容，默认值即可。

INTERFACE
Enter the Ethernet interface connected to the PPPoE 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):
现在系统要求询问你是否希望在没有联网的情况下，系统是否在空闲一段时间后，自动切断同网络的连接。我不喜欢这样，我希望在不用的时候，自己手动断掉连接。于是选择默认值，直接输入回车。

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):

接下来，要求你输入如何设置DNS参数，我选择的是输入：server。

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.
Enter the DNS information here: server

现在，要求你输入对应于帐户的密码,系统会让你输入两次密码确认。

PASSWORD
Please enter your Password: xxxxxx
Please re-enter your Password: xxxxxx

对于下面的提问，你可以不予理会，使用系统的默认参数即可。

USERCTRL
Please enter 'yes' (three letters, lower-case.) if you want to allow
normal user to start or stop DSL connection (default yes):

下面要求你输入防火墙的选择，我选择了没有使用防火墙。

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

现在它要求你确定是否在系统启动时自动去拨号，一般来讲，这是一种浪费，所以我们选择输入默认值，直接输入回车即可。

Start this connection at boot time
Do you want to start this connection at boot time?
Please enter no or yes (default no):

现在，系统开始总结你设置的参数。要求你确认，此时，你可以输入一个小y来确认。

** Summary of what you entered **

Ethernet Interface: eth0
User name: *sunzhou_110
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)

好了，当你看到这句话表明你的参数设置结束了。

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.

但是，此时你还无法联网，你必须手动建立连接，此时需要运行pppoe-connect命令。如果你看到了类似下面的输出表明你可以上网了。

[root@cynicholas ~]# pppoe-connect
RTNETLINK answers: No such process
Using interface ppp0
Connect: ppp0 <--> /dev/pts/2
PAP authentication succeeded
local  IP address 121.228.29.197
remote IP address 218.4.77.56
primary   DNS address 61.177.7.1
secondary DNS address 221.228.255.1

此时你可以运行下面的命令，如果看到域名被正确解析且有回应，则一切OK

[root@cynicholas ~]# ping www.baidu.com
PING www.a.shifen.com (119.75.218.45) 56(84) bytes of data.
64 bytes from 119.75.218.45: icmp_req=1 ttl=56 time=29.6 ms
64 bytes from 119.75.218.45: icmp_req=2 ttl=56 time=30.2 ms
64 bytes from 119.75.218.45: icmp_req=3 ttl=56 time=29.3 ms
64 bytes from 119.75.218.45: icmp_req=4 ttl=56 time=29.3 ms
64 bytes from 119.75.218.45: icmp_req=5 ttl=56 time=30.0 ms
64 bytes from 119.75.218.45: icmp_req=6 ttl=56 time=28.7 ms

最后，如果需要断掉连接，可以运行下面这个命令：

[root@cynicholas~]# pppoe-stop

Terminating on signal 15

Connect time 0.6 minutes.

Sent 2558 bytes, received 2166 bytes.

cat: /var/run/pppoe-adsl.pid.start: No such file or directory

pppoe: read (asyncReadFromPPP): Session 5001: Input/output error

如果你看到了最后一行的错误报告，不予理会它。

OK,一切大功告成。