RE: CHAP / PAP unidirectional authentication

Your debug output from R4 line 6 says " Using hostname from unknown
source" can you add on R4 "ppp chap sent-username R4 password 0 cisco"

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Matt Sherman
Sent: Monday, May 09, 2011 10:09 AM
To: Cisco certification
Subject: CHAP / PAP unidirectional authentication

Hi,

I'm having some problems with CHAP / PAP authentication. Can anyone
take a
look to see what I'm doing wrong - much appreciated. Here's the
scencario:

************************************************************************
*****
*************************************************
Configure a point-to-point link between R3 (s1/0.304) and R4 (s1/0.403)
with
the following authentication parameters:

* R3 should send a challenge when it is called by R4

* R4 should use PAP authentication when it is called by R3

* The password for CHAP authentication should be cisco, whereas, the
password for PAP should be set to ciscoPAP and the hostname should be
configured to be R3-PAP.
************************************************************************
*****
*************************************************

Here's my config which doesn't work:

************************************************************************
*****
*************************************************

*R3
*hostname R3

!
username R4 password 0 cisco
!
interface Serial1/0.304 point-to-point
 frame-relay interface-dlci 304 ppp Virtual-Template9
!
interface Virtual-Template9
 ip address 192.168.34.3 255.255.255.0
 ppp authentication chap callin
 ppp pap sent-username R3 password 0 ciscoPAP

*R4*

hostname R4
!
username R3 password 0 ciscoPAP
!
interface Serial1/0.403 point-to-point
 frame-relay interface-dlci 403 ppp Virtual-Template9
!
interface Virtual-Template9
 ip address 192.168.34.4 255.255.255.0
 ppp authentication pap callin
 ppp chap password 0 cisco
************************************************************************
*****
*************************************************

Here are the debug logs:

************************************************************************
*****
*************************************************

R3#debug ppp authentication
PPP authentication debugging is on
R3#
*Mar 1 01:14:46.547: Vi2 PPP: Authorization required
*Mar 1 01:14:46.647: Vi2 PAP: Using hostname from interface PAP
*Mar 1 01:14:46.651: Vi2 PAP: Using password from interface PAP
*Mar 1 01:14:46.651: Vi2 PAP: O AUTH-REQ id 37 len 16 from "R3"
*Mar 1 01:14:46.655: Vi2 CHAP: O CHALLENGE id 37 len 23 from "R3"
*Mar 1 01:14:46.759: Vi2 CHAP: I RESPONSE id 37 len 23 from "R4"
*Mar 1 01:14:46.763: Vi2 PAP: I AUTH-NAK id 37 len 26 msg is
"Authentication failed"

R4#debug ppp authentication
PPP authentication debugging is on
R4#
*Mar 1 01:15:59.763: Vi3 PPP: Authorization required
*Mar 1 01:15:59.955: Vi3 PAP: I AUTH-REQ id 63 len 16 from "R3"
*Mar 1 01:15:59.959: Vi3 PAP: Authenticating peer R3
*Mar 1 01:15:59.963: Vi3 CHAP: I CHALLENGE id 63 len 23 from "R3"
*Mar 1 01:15:59.971: Vi3 PPP: Sent PAP LOGIN Request
*Mar 1 01:15:59.983: Vi3 CHAP: Using hostname from unknown source
*Mar 1 01:15:59.983: Vi3 CHAP: Using password from AAA
*Mar 1 01:15:59.983: Vi3 CHAP: O RESPONSE id 63 len 23 from "R4"
*Mar 1 01:15:59.983: Vi3 PPP: Received LOGIN Response FAIL
*Mar 1 01:15:59.983: Vi3 PAP: O AUTH-NAK id 63 len 26 msg is
"Authentication failed"

Blogs and organic groups at http://www.ccie.net
Received on Mon May 09 2011 - 11:10:18 ART