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New Member

ISDN:One site calling multiple sites

I have a single site that should call 2 different remote site but at different times.

My plan is that they ping different ip addresses to start up the ISDN link to preferred site. I have created access list for this purpose. Also both sites have different ISDN phone Numbers.

On the single site, I have configured:

username xxxxx password xxxx

username xxxx password xxxx


interface BRI0/0

no ip address

encapsulation ppp

dialer idle-timeout 300

dialer enable-timeout 5

dialer map ip x.x.x.x name Maryland broadcast 001111111

dialer map ip y.y.y.y name Florida broadcast 001222222

dialer-group 1

dialer-group 2

isdn switch-type basic-net3

ppp authentication chap


access-list 10 permit

access-list 20 permit

access-list 100 permit ip x.x.x.x

access-list 101 permit ip x.x.x.x

dialer-list 1 protocol ip list 10

dialer-list 2 protocol ip list 20

dialer-list 1 protocol ip list 100

dialer-list 2 protocol ip list 101

The idea behind the above is that I have to configure this router offsite and send it out. And I will not have any real forum to test it here.


*Is the above correct.

*Do I need the standard access-list or the extended.

*Can I configure 2 dialer group and attach it to the single interface as I wrote above.

*Can I have 2 dialer list like the above.

* So when the user ping, it should start the connection to Maryland

*When the user ping, it should start up the connection to Florida

*Will this work?

Thanks for your help.

Cisco Employee

Re: ISDN:One site calling multiple sites

The config is not correct. The ip address is not present under the bri interface. You can't have a two dialer-group command under a single interface. So to answer all your questions, following url have a sample config for "One router dialing to multiple sites".

Go for similar config using dialer interface for each site. Let me know if you have more questions,.

New Member

Re: ISDN:One site calling multiple sites

Thanks Tepatel.

Really appreciate the page.

I have since created 2 interface Dialer (1 & 2). My questions are

1. Only the central site will be calling the 2 remote sites. Calls will not be initiated from the 2 remote sites. Will I still need to enter phone numbers on the remote routers?

2. As I have loopback addresses on the routers, can I use the ip unnumbered Loopback0?