FAQ-An AR2240 Cannot Obtain an IP Address Using PPPoE Dial-Up Due to an Incorrect Configuration

Publication Date:  2015-08-19 Views:  480 Downloads:  0
Issue Description
An AR2240 functions as the egress gateway on an enterprise's intranet, and connects to a carrier's network. The AR2240 connects to the Internet through a PPPoE server. After the configuration is complete, the AR2240 cannot obtain an IP address through PPP negotiation. When a PC directly connects to the carrier network, the PPPoE dial-up succeeds.



The configuration is as follows:

#                                                                 
dialer-rule                                                        
dialer-rule 1 ip permit
#
interface Dialer1                                                    
link-protocol ppp                                                   
ip address ppp-negotiate                                            
dialer user user2                                                   
ppp chap user user1                                                 
ppp chap password cipher user1                                      
dialer bundle 1                                                     
dialer queue-length 8                                               
dialer timer idle 300                                               
dialer-group 1       
#
interface Ethernet2/0/0
pppoe-client dial-bundle-number 1 on-demand
#
ip route-static 0.0.0.0 0 Dialer1
#
return
Solution
Because the PPPoE dial-up succeeds when a PC directly connects to the carrier network, the fault occurs on the AR2240.

Run the display pppoe-client session summary command. The command output shows that no PPPoE session is established.

<Huawei> display pppoe-client session summary
PPPoE Client Session:
ID   Bundle  Dialer  Intf             Client-MAC    Server-MAC    State

Run the display pppoe-client session packet command. The command output shows that no PPPoE packet statistics exist.

<Huawei> display pppoe-client session packet
PPPoE Client Session:                                                
ID     InP        InO        InD         OutP       OutO       OutD

Run the display this command to check the configuration of the device. The command output shows that the PPPoE dial-up mode is set to on-demand dial-up.

[Huawei] interface Ethernet2/0/0
[Huawei-Ethernet2/0/0] display this
[V200R005C30] 
#
interface Ethernet2/0/0
pppoe-client dial-bundle-number 1 on-demand
#
return

The intranet interface Ethernet 1/0/0 of the AR2240 is in Down state and no packet is transmitted through the interface.

<Huawei> display interface Ethernet 1/0/0
Ethernet1/0/0 current state : DOWN                                   
Line protocol current state : DOWN

The configuration is incorrect. If the dial-up interface is configured to work in on-demand dial-up mode, the device initiates a PPPoE call and sets up a PPPoE session only when it needs to transmit data. However, the intranet interface on the device is Down. No data can be transmitted through this interface and no PPPoE call will be triggered to set up a PPPoE session.

Change the PPPoE dial-up mode to permanently online. This configuration ensures that the device initiates a PPPoE call and sets up a PPPoE session immediately after the interface connected to the carrier network is Up. After the configuration is changed, the AR2240 can successfully dial up to the Internet.

[Huawei] interface Ethernet2/0/0
[Huawei-Ethernet2/0/0] pppoe-client dial-bundle-number 1

END