IP only over DDR

[j-allison]

This dial-up line is a ISDN 64K and the remote site is using this ISDN for DDR backup for the serial line to the central office. The serial line goes down +- every second week for a few munitues so the ISDN is critical for network operation. The remote site has IP, IPX clients and SNA user with DLSW configured. When the serial link goes down, the IP traffic is priority 1 and all other protocols should not cross the ISDN DDR link. How can we endure that ONLY IP trqaffic cross the ISDN link when active.

Regards,

Jacques Allison

[cketan]

DDR Backup using BRIs and the backup interface Command

http://www.cisco.com/warp/public/793/access_dial/britobribackup.html

Permit only IP to cross over as interesting traffic in the access-list

Regards...Ketan Chaudhari, CCSA, CCNP, MCSE

[j-allison]

Thanks for the suggestion, but this is not the answer I'm looking for. The interesting traffic defined by the access list is only to specify which traffic will bring up the BRI interface of the primary link goes down. When the link is UP with the above configuration, all other traffic will cross the ISDN line. I want to make sure that only IP cross the link when it’s active. What is the best debug command to check the packets crossing the line? Which access-list on the BRI interface in and out will work the bets?

Regards,

Jacques Allison

CCNP+Security, CCDP, MCSE

[svermill]

I would think that the same access list used to define interesting traffic could be applied to the BRI out. The router will still have to handle these packets, of course, before discarding them.