Troubleshooting Understanding PPPoE Interaction and PPPoE PADI Timeout
This Article Applies to:
All Omada routers.
Background:
The PPPoE (Point-to-Point Protocol over Ethernet) interaction involves several key steps, where PADI (PPPoE Active Discovery Initiation) is the first one. In the setup of PPPoE, the client and server side communicate through a series of messages to establish a connection. When a PADI timeout occurs, it typically means the PPPoE server did not respond to the client's PADI request.
Interaction:
1. PADI (PPPoE Active Discovery Initiation): The client sends a PADI packet to the broadcast address, looking for PPPoE servers.
2. PADO (PPPoE Active Discovery Offer): Upon receiving a PADI packet, the server sends back a PADO packet, indicating the server is available.
3. PADR (PPPoE Active Discovery Request): The client selects a server and sends a PADR packet to request the establishment of a session.
4. PADS (PPPoE Active Discovery Session-confirmation): The server responds to the PADR packet with a PADS packet to confirm the session, at which point a session ID is created.
5. Data Transmission: After the session is established, the client and server can exchange data via the PPP protocol.
(Optional) 6. PADT (PPPoE Active Discovery Terminate): When either the client or server wishes to terminate the session, they send a PADT packet.
Possible Reasons:
A PADI timeout typically occurs in the first step of interaction, where after the client(router) sends out a PADI request, it might not receive any PADO response from servers due to several reasons:
1. Network Issues: Connection problems between the client and server, such as line interruptions or signal degradation, might lead to the loss of PADI packets.
2. Server Unavailability: The target PPPoE server is overloaded, crashed, or undergoing maintenance, unable to respond to PADI packets.
3. Configuration Errors: Misconfigurations of the client or networking devices (like routers, DSLAMs, etc.) may prevent PADI packets from correctly reaching the server.
4. Physical Connection Problems: There could be issues with the physical connection between the client and the network, such as damaged Ethernet cables or mismatched interfaces.
If you face an error log, it is recommended you Wireshark and see if the PADO was received or not. If this is not received, or no response from the server at all, you should contact your ISP for further technical support.
Note:
The router is the client in this situation when dialing by PPPoE. The client is the ISP server which hosts the PPPoE server.
Update Log:
Mar 14th, 2024:
Release of this article.
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- If there is anything unclear in this solution post, please feel free to comment below.
- If you encounter such an issue, please follow the troubleshooting above to check your settings. Besides, ensure your Omada Controller and Gateway are running with the latest firmware.
- If the issue still exists after you try the suggestion above, please feel free to comment below or contact our support team with a detailed description of your issue and the steps you have tried.
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