Datasheet
Lab – Configuring Basic PPP with Authentication
© 2013 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 9 of 27
Branch1(config)# interface s0/0/0
Branch1(config-if)# encapsulation hdlc
d. Observe the debug PPP messages on the Branch1 router. The serial connection has terminated, and the
line protocol is down. The route to 10.1.1.2 (Central) has been removed from the routing table.
Jun 20 02:29:50.295: Se0/0/0 PPP DISC: Lower Layer disconnected
Jun 20 02:29:50.295: PPP: NET STOP send to AAA.
Jun 20 02:29:50.299: Se0/0/0 IPCP: Event[DOWN] State[Open to Starting]
Jun 20 02:29:50.299: Se0/0/0 IPCP: Event[CLOSE] State[Starting to Initial]
Jun 20 02:29:50.299: Se0/0/0 CDPCP: Event[DOWN] State[Open to Starting]
Jun 20 02:29:50.299: Se0/0/0 CDPCP: Event[CLOSE] State[Starting to Initial]
Jun 20 02:29:50.29
Branch1(config-if)#9: Se0/0/0 LCP: O TERMREQ [Open] id 7 len 4
Jun 20 02:29:50.299: Se0/0/0 LCP: Event[CLOSE] State[Open to Closing]
Jun 20 02:29:50.299: Se0/0/0 PPP: Phase is TERMINATING
Jun 20 02:29:50.299: Se0/0/0 Deleted neighbor route from AVL tree: topoid 0, address
10.1.1.2
Jun 20 02:29:50.299: Se0/0/0 IPCP: Remove route to 10.1.1.2
Jun 20 02:29:50.299: Se0/0/0 LCP: Event[DOWN] State[Closing to Initial]
Jun 20 02:29:50.299: Se0/0/0 PPP: Phase is DOWN
Branch1(config-if)#
Jun 20 02:30:17.083: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0,
changed state to down
Jun 20 02:30:17.083: %OSPF-5-ADJCHG: Process 1, Nbr 209.165.200.225 on Serial0/0/0
from FULL to DOWN, Neighbor Down: Interface down or detached
e. Observe the debug PPP messages on the Central router. The Central router continues to attempt to
establish a connection with Branch1 as indicated by the debug messages. When the interfaces are
unable to establish a connection, the interfaces go back down again. Furthermore, OSPF cannot
establish an adjacency with its neighbor due to the mismatched serial encapsulation.
Jun 20 02:29:50.296: Se0/0/0 PPP: Sending cstate DOWN notification
Jun 20 02:29:50.296: Se0/0/0 PPP: Processing CstateDown message
Jun 20 02:29:50.296: Se0/0/0 PPP DISC: Lower Layer disconnected
Jun 20 02:29:50.296: PPP: NET STOP send to AAA.
Jun 20 02:29:50.296: Se0/0/0 IPCP: Event[DOWN] State[Open to Starting]
Jun 20 02:29:50.296: Se0/0/0 IPCP: Event[CLOSE] State[Starting to Initial]
Jun 20 02:29:50.296: Se0/0/0 CDPCP: Event[DOWN] State[Open to Starting]
Jun 20 02:29:50.296: Se0/0/0 CDPCP: Event[CLOSE] State[Starting to Initial]
Jun 20 02:29:50.296: Se0/0/0 LCP: O TERMREQ [Open] id 2 len 4
Jun 20 02:29:50.296: Se0/0/0 LCP: Event[CLOSE] State[Open to Closing]
Jun 20 02:29:50.296: Se0/0/0 PPP: Phase is TERMINATING
Jun 20 02:29:50.296: Se0/0/0 Deleted neighbor route from AVL tree: topoid 0, address
10.1.1.1
Jun 20 02:29:50.296: Se0/0/0 IPCP: Remove route to 10.1.1.1
Jun 20 02:29:50.296: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.1.1 on Serial0/0/0 from
FULL to DOWN, Neighbor Down: Interface down or detached
Jun 20 02:29:50.296: Se0/0/0 LCP: Event[DOWN] State[Closing to Initial]
Jun 20 02:29:50.296: Se0/0/0 PPP: Phase is DOWN
Jun 20 02:29:52.296: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0,
changed state to down
.Jun 20 02:29:52.296: Se0/0/0 PPP: Sending cstate UP notification