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PPP not connecting over ISDN


I want to connect 2 routers together over an ISDN BRI link (64k).

I can connect; Layer 1 & 2 are working fine, however when it comes to establishing PPP i come to a hurdle.

The calling router:

1w3d: ISDN BR0/0: RX <- ALERTING pd = 8 callref = 0x8E

1w3d: ISDN BR0/0: RX <- CONNECT pd = 8 callref = 0x8E

1w3d: ISDN BR0/0: TX -> CONNECT_ACK pd = 8 callref = 0x0E

1w3d: %LINK-3-UPDOWN: Interface BRI0/0:1, changed state to u

1w3d: Dialer Watch: resetting call in progress on BR0/0:1

1w3d: BR0/0:1 PPP: Treating connection as a callout

1w3d: BR0/0:1 PPP: Phase is ESTABLISHING, Active Open

1w3d: BR0/0:1 LCP: O CONFREQ [Closed] id 122 len 34

Appears fine.

The called router:

18w6d: ISDN BR1/2: Event: Received a DATA call from <unknown> on B1 at 64 Kb/s

18w6d: ISDN BR1/2: Event: Accepting the call id 0x103

18w6d: %LINK-3-UPDOWN: Interface BRI1/2:1, changed state to up

18w6d: BR1/2:1 PPP: Using dialer call direction

18w6d: BR1/2:1 PPP: Treating connection as a callin

18w6d: BR1/2:1 PPP: Phase is ESTABLISHING, Passive Open [0 sess, 1 load]

18w6d: BR1/2:1 LCP: State is Listen

18w6d: ISDN BR1/2: TX -> CALL_PROC pd = 8 callref = 0x96

18w6d: Channel ID i = 0x89

18w6d: ISDN BR1/2: TX -> CONNECT pd = 8 callref = 0x96

18w6d: ISDN BR1/2: RX <- CONNECT_ACK pd = 8 callref = 0x16

18w6d: BR1/2:1 LCP: TIMEout: State Listen

18w6d: BR1/2:1 LCP: O CONFREQ [Listen] id 91 len 29

What worries me here is that after the called router has an outgoing CONFREQ. Ideally, this should be received from the calling router, therefore should be an incomming request.

If anyone has any ideas they'd be much appreciated.

Thanks in advance.



Re: PPP not connecting over ISDN

I would definitely take a look at outputs of,

debug ppp authentication

Please see if you can paste the output of the above debug. Also paste your show run at either ends.

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