From: Christopher M. Heffner (cheffner@certified-labs.com)
Date: Sun Aug 21 2005 - 08:03:21 GMT-3
I agree with Scott that you do have to watch the incoming dialing number
along with the name parameter for the dialer map. Typically the named
parameter is used when authenticating the remote peers. If the remote
peer is not setup for authentication then the router could be placing a
second call to forward the responds back too the other router.
I also noticed one other issues with your config, hopefully just cut and
paste/typing errors.
I noticed the router's ip addresses are 150.50.9.2 for both BRI
interfaces. You might want to double check you config.
HTH.
Christopher M. Heffner, CCIE 8211, CCSI 98760
Strategic Network Solutions, Inc.
VP of Internetworking Technologies
www.certified-labs.com
"Complete CCIE R&S and Security Online Rack Rentals"
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Arun Arumuganainar
Sent: Saturday, August 20, 2005 11:57 AM
To: 'Group Study'
Subject: ISDN Dialer Map does not support Bidirectional Traffic !!!
I was working with ISDN !!! I came up on a problem !!!
My Topology looks like this .
R2--------------R5
Bri0/0 Bri0/0
My configurations goes like this
Router 2
isdn switch-type basic-net3
int bri0/0
ip address 150.50.9.2 255.255.255.252
dialer map ip 150.50.9.5 name Router-5 broadcast 5552000
dialer-group 1
dialer-list 1 protocol ip permit
===============================================
Router 5
isdn switch-type basic-net3
int bri0/0
ip address 150.50.9.2 255.255.255.252
dialer map ip 150.50.9.5 name Router-2 broadcast 5551000
dialer-group 1
dialer-list 1 protocol ip permit
===============================================
After configuring like this when I send ping packets from Router 2 to
Router
5 . I observe a strange behaviour !!! Forward traffic goes via one BRI
channel and Return traffic goes via another !!!
The behaviour is same when
a) I ping on either directions ( i.e R2-R5 and also From R5 to R2 ) .
b) The behaviour is observed with both HDLC and PPP encapsulaton ( IP
Expert Protor Guide Say with PPP encap. traffic per bri channel should
be bi-directional ) . But I could not notice this !!!
When I removed dialer map on one side !!! Packet from the other side
reaches it . But the return traffic is dropped due to encapsulation
failure ( I observed this with debug ip pack ) !!!
One work around for this : use dialer string instead of dialer maps !!!
With Dialer strings I am able to achive two way traffic using single BRI
channel for both HDLC and also PPP Encapsulations !!!!
I am wondering is this the right behavior ???!!!! It would be great if
any body can clarify !!!
Thanks and Regards
Arun
This archive was generated by hypermail 2.1.4 : Sun Sep 04 2005 - 17:01:19 GMT-3