Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

ISDN dialup through PRI and BRI


The scenario is as follows.

HO(head office) will have 1 isdn PRI no. and 1 isdn BRI no (spare in case of ISDN Pri

down). The PRI is attached to Cisco 7206 whereas the ISDN bri will reside on a Cisco2600 router in HO LAN. There are actually two routers at HO.

Stores will have 1 isdn BRI no.

Can Stores call HO using these two ISDN numbers. Stores will call the Pri

no. as the main line and Bri as the backup line in case the Pri does not


Can i add the the additional command? Will it work? How is the precedence


Store ISDN config is as follows

interface Dialer1

bandwidth 64

ip address

encapsulation ppp

ip tcp header-compression iphc-format

no ip mroute-cache

dialer pool 1

dialer remote-name HQ

dialer string 77184094 (Pri no)

dialer string xxxxxxx (Bri no)

dialer-group 1

ppp authentication chap

ppp multilink

ppp multilink fragment-delay 10

ppp multilink interleave

ip rtp header-compression iphc-format

ip rtp priority 16384 16383 48

Ip route dialer 1 180




Re: ISDN dialup through PRI and BRI

Based on the availability of the PRI or ISDN the config will function, And it will not be a true backup for PRI line. Supose when the Stores ISDN line dials and the one of the PRI line which it dials was busy, it will try the next string in the interface dilaer configurattion and gets established if the ISDN line in the CO is free. Hence it will not be a true backup for the PRI for the purpose of breakdown.

CreatePlease login to create content