1. Forum
  2. Usenet
  3. COMP.PROTOCOLS.PPP

  • LCP DOWN not notified by pppd when LCP Conf request is received during

    From sreerajsarma@gmail.com@21:1/5 to All on Sat Apr 23 23:20:56 2016
    Hi

    Have a query regarding pppd behaviour when LCP Conf request is received during LCP open state

    pppd version used is 2.4.5

    HW : Linux(running pppd 2.4.5) ========== Cisco MWR switch terminating ppp.


    pppd Logs
    ============

    LCP negotiation is started.

    sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x5a064c51> <pcomp> <accomp> <mrru 1500> <endpoint [IP:14.20.20.1]>]
    rcvd [LCP ConfReq id=0xca <magic 0xe0148a35> <pcomp> <accomp> <mrru 1500> <endpoint [local:4d.4c.50.50.50.34]>]
    sent [LCP ConfAck id=0xca <magic 0xe0148a35> <pcomp> <accomp> <mrru 1500> <endpoint [local:4d.4c.50.50.50.34]>]
    sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x5a064c51> <pcomp> <accomp> <mrru 1500> <endpoint [IP:14.20.20.1]>]
    rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x5a064c51> <pcomp> <accomp> <mrru 1500> <endpoint [IP:14.20.20.1]>]

    LCP is in open state now

    sent [LCP EchoReq id=0x0 magic=0x5a064c51]


    IPCP negotiation is started.

    sent [IPCP ConfReq id=0x1 <addr 14.20.20.1>]
    rcvd [IPCP ConfAck id=0x1 <addr 14.20.20.1>]

    During this phase LCP Conf Request is received from the peer side (Cisco MWR)

    rcvd [LCP ConfReq id=0xcb <magic 0xe0148a35> <pcomp> <accomp> <mrru 1500> <endpoint [local:4d.4c.50.50.50.34]>]
    sent [LCP ConfReq id=0x2 <asyncmap 0x0> <magic 0xdde160a5> <pcomp> <accomp> <mrru 1500> <endpoint [IP:14.20.20.1]>]
    sent [LCP ConfAck id=0xcb <magic 0xe0148a35> <pcomp> <accomp> <mrru 1500> <endpoint [local:4d.4c.50.50.50.34]>]
    rcvd [LCP ConfAck id=0x2 <asyncmap 0x0> <magic 0xdde160a5> <pcomp> <accomp> <mrru 1500> <endpoint [IP:14.20.20.1]>]

    LCP is again renegotiated and goes to open state.

    But LCP was already in open state and pppd did not notify upper layers about this re negotiation.

    Can anybody clarify , Is this behaviour expected OR somehow pppd is notifying upper layers but it is to be verified in some other log ?

    Regards,
    Sreeraj

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Manikandaprabu Kuppannan@21:1/5 to All on Fri Nov 10 05:48:49 2017
    Hi Sreeraj,

    In my opinion, this is expected behaviour.
    Not needed to inform upper layer about renegotiation.
    I assume your question is not about renegotiation in a loop.

    Thanks,
    ManikandaPrabu

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)