linux ADSL 安装

前提：

一、安装的前提条件

1.确保安装了网卡并工作正常使用命令#ifconfig eth0 查看网卡状态

2.在系统中不要设置默认路由(网关),让ADSL拨号后自动获得

如果已经设置了默认路由,使用以下方法删除: 在文件 /etc/sysconfig/network/ifconfig-eth0 中删除 GATEWAY= 这一行,然后以root执行:

# service network restart

3.已经安装了pppd软件包

如果存在文件 /usr/sbin/pppd,则说明已经安装了pppd; 如果未安装,下载安装这个软件包

二、安装CentOS PPPOE客户端软件

Linux下的CentOS PPPOE客户端软件比较多,而且大多使用GNU License,我们推荐使用rp-pppoe这个软件包。从http://www.roaringpenguin.com/pppoe/这个网站上，不仅可以下载各发布包下的rp-pppoe的二进制软件包，而且可以下载源代码软件包。我们使用centos下的yum安装方法,来安装rp-pppoe软件包

#yum -y install rp-pppoe

三、设置并启动CentOS PPPOE客户端软件

#adsl-setup  设置ADSL（有些没有该命令，可以用 /usr/sbin/pppoe-setup 设置）

#adsl-start  /etc/sysconfig/network-scripts/ifcfg-ppp0  打开ADSL连接

#ifup ppp0  开启

#ifdown ppp0  关闭

#adsl-status 查当前连接状态

#adsl-stop

帐号和密码一般保存在 /etc/ppp/chap-secrets 或  /etc/ppp/pap-secrets 中

详解：adsl-setup

安装完软件包后，必须配置CentOS PPPOE的配置文件/etc/ppp/pppoe.conf，从而让ADSL拨号时使用配置文件中的用户名、密码等参数。我们不必手工改动这个文件，可以使用adsl-setup这个工具进行配置：#/usr/sbin/adsl-setup 当出现 >> Enter your PPPoE user name : 输入ADSL帐号的用户名
当出现 >>> 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 ethn, where 'n' is a number. (default eth0): 输入 eth0 ,这是ADSL相连的网卡的名字
当出现 >>> Enter the demand value (default no): 输入 no
当出现 >>> Enter the DNS information here: 输入 server ,这表示使用ADSL拨号自动获得的DNS服务器IP地址
当出现 >>> Please enter your PPPoE password: 输入ADSL帐号的密码
当出现 >>> Choose a type of firewall (0-2): 输入 0 ，不使用防火墙
当出现 >>> Accept these settings and adjust configuration files (y/n)? 如果输入的信息正确，输入 y ,完成配置，否则，输入 n 重新输入。

[root@localhost ~]# adsl-setup　 ← 建立ADSL连接
Welcome to the ADSL client setup. First, I will run some checks on
your system to make sure the PPPoE client is installed properly...
 
 
LOGIN NAME
 
Enter your Login Name (default root):　← 填入ADSL连接的用户名
 
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):　　← 指定网络接入设备，一块网卡的情况下，一般为默认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):　　← 直接按回车，接受默认设置
 
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:　　← 如果知道DNS服务器的信息在此填入。不知道的情况按回车跳过
 
PASSWORD
 
Please enter your Password:　← 输入ADSL的连接密码
Please re-enter your Password:　← 再次确认输入ADSL的连接密码
 
USERCTRL
 
Please enter 'yes' (two letters, lower-case.) if you want to allow
normal user to start or stop DSL connection (default yes): no　← 填入no，不允许一般用户控制PPPoE的连接
 
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　← 输入0，不在这里使用防火墙
 
Start this connection at boot time
 
Do you want to start this connection at boot time?
Please enter no or yes (default no): yes　← 填入yes，在系统启动时自动连接ADSL
 
** Summary of what you entered **
 
Ethernet Interface: eth0
User name: caun870293@ca.dti.ne.jp
Activate-on-demand: No
DNS: Do not adjust
Firewalling: NONE
User Control: no
Accept these settings and adjust configuration files (y/n)? y　← 配置信息确认无误后，键入y同意设置
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/adsl-status /etc/sysconfig/network-scripts/ifcfg-ppp0'
to see the link status.
 

四、启动CentOS PPPOE客户端软件

[root@localhost ~]# adsl-start 　← 启动ADSL连接
 
[root@localhost ~]# 　　← 稍等片刻后若启动成功后出现提示符（无任何提示即意味着连接成功）

使用命令 /usr/sbin/adsl-start 启动CentOS PPPOE客户端软件,进行连接，如果成功，将出现 Connected; 如果不成功，请检查网线、ADSL MODEM等物理设备，并查看 /var/log/messages中的信息
/usr/sbin/adsl-stop 关闭和ISP的连接
/usr/sbin/adsl-status 查看当前连接的状态

如果想在Linux系统启动时自动启动ADSL连接，输入以下命令 #chkconfig --add adsl将在当前的运行级下加入ADSL的自启动脚本