CCIE Pursuit Blog

January 6, 2008

Internetwork Expert Volume III: Lab 1 – Section 3

3 WAN Technologies

3.1 Hub and Spoke

This was an easy Hub and Spoke configuration.  The only gotcha is that the initial configurations have some of the FR ports configured with an IP address and opened up.  That means that FR Inverse-ARP is in play:

Before configuration:

r5(config)#do sh run int s0/0
interface Serial0/0
 ip address 140.1.245.5 255.255.255.0
 encapsulation frame-relay
end

r5(config)#do sh frame map
Serial0/0 (up): ip140.1.245.2 dlci 502(0x1F6,0x7C60), dynamic,
              broadcast,, status defined, active
Serial0/0 (up): ip 140.1.245.4 dlci 504(0x1F8,0x7C80), dynamic,
              broadcast,, status defined, active 

3.2 Point-To-Point

This was a very basic point-to-point Frame Relay configuration.

3.3 PPP Authentication

PPP is usually a time-waster for me.  I have boned up on the topic a bit and this task was very basic, so I had little trouble except for my own undoing: 

r5:
username r4 password 0 CISCO
!
interface Serial0/1
 description ->r4 PTP DTE PPP
 ip address 140.1.45.5 255.255.255.0
 encapsulation ppp
 ppp authentication chap

Debugging ppp authentication:
*Mar  1 04:14:18.396: Se0/1 PPP: Authorization required
*Mar  1 04:14:18.400: Se0/1 CHAP: O CHALLENGE id 13 len 23 from “r5”
*Mar  1 04:14:18.400: Se0/1 CHAP: I CHALLENGE id 19 len 23 from “r4”
*Mar  1 04:14:18.404: Se0/1 CHAP: Using hostname from unknown source
*Mar  1 04:14:18.404: Se0/1 CHAP: Using password from AAA 
*Mar  1 04:14:18.404: Se0/1 CHAP: O RESPONSE id 19 len 23 from “r5”

The link would not come up.  The fact that it was trying to use an AAA password made me suspect that I had misconfigured the password.  Close, I actually mucked up the username on r4:

r4(config-if)#do sh run | i username
username r4
password 0 CISCO

r4(config-if)#no username r4 password 0 CISCO
r4(config)#user r5pass CISCO
r4(config)#
*Mar  1 04:15:26.552: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/1, changed state to up

This is what the debug looks like when PPP CHAP authentication is successful:

Se0/1 PPP: Using default call direction
Se0/1 PPP: Treating connection as a dedicated line
Se0/1 PPP: Session handle[C1000004] Session id[62]
Se0/1 PPP: Authorization required
Se0/1 CHAP: O CHALLENGE id 56 len 23 from “r5”
Se0/1 CHAP: I CHALLENGE id 62 len 23 from “r4”
%LINK-3-UPDOWN: Interface Serial0/1, changed state to up
Se0/1 CHAP: Using hostname from unknown source
Se0/1 CHAP: Using password from AAA
Se0/1 CHAP: O RESPONSE id 62 len 23 from “r5”
Se0/1 CHAP: I RESPONSE id 56 len 23 from “r4”
Se0/1 PPP: Sent CHAP LOGIN Request
Se0/1 PPP: Received LOGIN Response PASS
Se0/1 PPP: Sent LCP AUTHOR Request
Se0/1 PPP: Sent IPCP AUTHOR Request
Se0/1 LCP: Received AAA AUTHOR Response PASS
Se0/1 IPCP: Received AAA AUTHOR Response PASS
Se0/1 CHAP: O SUCCESS id 56 len 4
Se0/1 CHAP: I SUCCESS id 62 len 4
Se0/1 PPP: Sent CDPCP AUTHOR Request
Se0/1 PPP: Sent IPCP AUTHOR Request
Se0/1 CDPCP: Received AAA AUTHOR Response PASS
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/1, changed state to up

Advertisements

Leave a Comment »

No comments yet.

RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Create a free website or blog at WordPress.com.

%d bloggers like this: