系统环境：
[root@foundation33 network-scripts]# uname --all
Linux foundation33.ilt.example.com 3.10.0-229.el7.x86_64 #1 SMP Thu Jan 29 18:37:38 EST 2015 x86_64 x86_64 x86_64 GNU/Linux
红帽版本7.0
安装pppoe
[root@foundation33 network-scripts]# yum search pppoe
rp-pppoe.x86_64 : A PPP over Ethernet client (for xDSL support)
# rpm -qd rp-pppoe
/usr/share/doc/rp-pppoe-3.11/pap-secrets
/usr/share/doc/rp-pppoe-3.11/pppoe-connect
/usr/share/doc/rp-pppoe-3.11/pppoe-init
/usr/share/doc/rp-pppoe-3.11/pppoe-setup
/usr/share/doc/rp-pppoe-3.11/pppoe-start
/usr/share/doc/rp-pppoe-3.11/pppoe-status
/usr/share/doc/rp-pppoe-3.11/pppoe-stop
pppoe的相关程序
执行：pppoe-setup
Welcome to the PPPoE 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):###此处为运营商给你的帐号
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): br0###注意，此处为桥接接口，不要填你的真实网卡接口和eth0
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
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##填写server表示自动获取dns
Please enter your Password:
Please re-enter your Password:##你的密码
Please enter 'yes' (three letters, lower-case.) if you want to allow
normal user to start or stop DSL connection (default yes):
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): 选0不设定防火墙规则
[root@foundation33 network-scripts]# /sbin/ifup ppp0
[root@foundation33 network-scripts]# ifup status
/usr/sbin/ifup: configuration for status not found.
Usage: ifup <configuration>
[root@foundation33 network-scripts]# pppoe-status
pppoe-status: Link is up and running on interface ppp0
64: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1492 qdisc pfifo_fast state UNKNOWN qlen 3
link/ppp
inet 10.12.191.19 peer 10.12.188.1/32 scope global ppp0
valid_lft forever preferred_lft forever
这样，你就可以正常的上网了，试一试ping baidu吧！
注意，可以在ifup status 启动是在另一个终端中执行pppoe-status可以方便的查出问题出在那里。
