PPPoE Dial-up Fails on an AR2220

Publication Date:  2015-08-18 Views:  749 Downloads:  0
Issue Description
As shown in the following figure, when an AR2220 functions as a PPPoE client, a user cannot access the Internet using PPPoE dial-up.

The dial-up configuration is as follows:
interface Dialer1
link-protocol ppp
ppp chap user client
ppp chap password cipher %@%@<Ce:T{<iyOSzrkKH5<[8*![A%@%@
ppp ipcp dns request
ip address ppp-negotiate
dialer user server
dialer bundle 1
dialer-group 1
nat outbound 2000
Handling Process
1.  The configuration on the interface shows that the authentication mode configured on the interface is CHAP. However, the authentication mode configured on the server is unknown.

2.  Run the debugging pppoe-client command to enable debugging. The debugging information shows that the authentication fails. The server uses PAP authentication mode. The authentication fails because the authentication modes on the client and server are different.

3.  Run the ppp pap local-user client password cipher client123 command on Dialer1 to set the authentication mode to PAP. The fault is then rectified.
PPPoE authentication will fail if inconsistent PPP authentication modes are used on the PPPoE server and client. It is recommended that you configure both CHAP and PAP authentication modes on the AR router. The AR router will dynamically determine the authentication mode based on packets exchanged with the PPPoE server.