CentOS6以后要安装rp-pppoe这个软件，centos之前的版本是adsl-setup命令安装。
（1）查看是否安装
#rpm-qa|greprp-pppoe
没有内容输出则没安装，若可以联网使用#yuminstallrp-pppoe
无法联网则：CentOS安装盘放入光驱
挂载光盘
#mount/dev/cdrom/media
找出文件路径
#find/media-name'rp-pppoe*'
这个文件没有依赖项，可以直接安装
#rpm-ivh/media/CentOS_6.5_Final/Packages/rp-pppoe-3.10-8.el6.i686.rpm
（2）设置拨号
#whereispppoe-setup
#/sbin/pppoe-setup
或#pppoe-setup
开始设置ADSL和DNS信息：
WelcometothePPPoEclientsetup.First,Iwillrunsomecheckson
yoursystemtomakesurethePPPoEclientisinstalledproperly...
ThefollowingDSLconfigwasfoundonyoursystem:
Device:Name:
ppp0DSLppp0
PleaseenterthedeviceifyouwanttoconfigurethepresentDSLconfig
(defaultppp0)orenter'n'ifyouwanttocreateanewone:ppp0
LOGINNAME
EnteryourLoginName(defaultroot):中国电信或者网通给你的ADSL用户名，注意电信给的有ad打头
INTERFACE
EntertheEthernetinterfaceconnectedtothePPPoEmodem
ForSolaris,thisislikelytobesomethinglike/dev/hme0.
ForLinux,itwillbeethX,where'X'isanumber.
(defaulteth0):eth0←指定网络接入设备，一块网卡的情况下，一般为默认eth0
Doyouwantthelinktocomeupondemand,orstayupcontinuously?
Ifyouwantittocomeupondemand,entertheidletimeinseconds
afterwhichthelinkshouldbedropped.Ifyouwantthelinkto
stayuppermanently,enter'no'(twoletters,lower-case.)
NOTE:Demand-activatedlinksdonotinteractwellwithdynamicIP
addresses.Youmayhavesomeproblemswithdemand-activatedlinks.
Enterthedemandvalue(defaultno):←直接按回车，接受默认设置，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。
DNS
PleaseentertheIPaddressofyourISP'sprimaryDNSserver.
IfyourISPclaimsthat'theserverwillprovidedynamicDNSaddresses',
enter'server'(alllower-case)here.
Ifyoujustpressenter,Iwillassumeyouknowwhatyouare
doingandnotmodifyyourDNSsetup.
EntertheDNSinformationhere:202.96.209.5第一个DNS建议手动设置，不然可能连不上（或EntertheDNSinformationhere:server//PPPOE拨号的输入server即可，即动态获得DNS）
PleaseentertheIPaddressofyourISP'ssecondaryDNSserver.
Ifyoujustpressenter,IwillassumethereisonlyoneDNSserver.
EnterthesecondaryDNSserveraddresshere:202.96.209.133第二个DNS建议手动设置，不然可能连不上
PASSWORD
PleaseenteryourPassword:输入ADSL的连接密码
Pleasere-enteryourPassword:←再次确认输入ADSL的连接密码
USERCTRL
Pleaseenter'yes'(threeletters,lower-case.)ifyouwanttoallow
normalusertostartorstopDSLconnection(defaultyes):yes←填入no，不允许一般用户控制PPPoE的连接
FIREWALLING
Pleasechoosethefirewallrulestouse.Notethattheserulesare
verybasic.Youarestronglyencouragedtouseamoresophisticated
firewallsetup;however,thesewillprovidebasicsecurity.Ifyou
arerunninganyserversonyourmachine,youmustchoose'NONE'and
setupfirewallingyourself.Otherwise,thefirewallruleswilldeny
accesstoallstandardserverslikeWeb,e-mail,ftp,etc.Ifyou
areusingSSH,theruleswillblockoutgoingSSHconnectionswhich
allocateaprivilegedsourceport.
Thefirewallchoicesare:
0-NONE:Thisscriptwillnotsetanyfirewallrules.Youareresponsible
forensuringthesecurityofyourmachine.YouareSTRONGLY
recommendedtousesomekindoffirewallrules.
1-STANDALONE:Appropriateforabasicstand-aloneweb-surfingworkstation
2-MASQUERADE:AppropriateforamachineactingasanInternetgateway
foraLAN
Chooseatypeoffirewall(0-2):0←输入0，不在这里使用防火墙
Startthisconnectionatboottime
Doyouwanttostartthisconnectionatboottime?
Pleaseenternooryes(defaultno):yes←填入yes，在系统启动时自动连接ADSL
Acceptthesesettingsandadjustconfigurationfiles(y/n)?y←配置信息确认无误后，键入y同意设置
**Summaryofwhatyouentered**
EthernetInterface:eth0
Username:
[root@localhost~]#pppoe-start←启动ADSLpppoe连接（或#ifupppp0//启动ppp0接口）
[root@localhost~]#pppoe-status设置完成后我们看看adsl状态