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Forum Replies

  1. system says:

    Have you ever encountered this scenario?

    Jan 15 15:23:36.968: Se0/2/0:0 LCP: I PROTREJ [Open] id 1 len 10 protocol CDPCP (0x820701010004)
    Jan 15 15:23:36.968: Se0/2/0:0 CDPCP: State is Closed
    Jan 15 15:23:36.968: Se0/2/0:0 CDPCP: State is Listen

    And because of this, interface is not bundling up in a multilink. As you can see that the inbound packet is telling the device that the protocol CDPCP is being rejected.

  2. Hi Ali,

    Do you have the complete debug for this? Normally I only see this when the PPP session is going down, for example when authentication fails or something.


  3. maher1 says:

    Hi Matt W,

    The Magic number is randomly generated and provides a way to detect looped-back links and other Data Link Layer anomalies. This Configuration Option may be required by some other Configuration Options such as the Link-Quality-Monitoring Configuration Option.

    When the node sends PPP LCP messages, these messages may include a magic number. If a line is looped, the node receives an LCP message with its own magic number, instead of getting a message with the peer's magic number.

    Now what is looped? For this I give you an example: To test a circuit, the phone company might loop the circuit.This means that the phone company takes the electrical signal sent by the CPE device and sends the same electrical current right back to the same device.
    As for routers, they cannot send bits to each other while the link is looped. The router might not notice that the link is looped, because the router is still receiving something over the link! PPP helps the router recognize a looped link quickly

    I hope I could answer your question.

  4. How about a PAP example too? I used the following commands:

    Username TRINITY password cisco

    int s0/0
       encapsulation ppp
       ppp authentication pap
       ppp pap sent-username NEO password cisco

    But I get the following error:

    AAA/AUTHEN/PPP (0000010F): Pick method list 'default'

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