ISDN IP Routing - Help !!!

[fkseow]

I have three sites; Sites A, B & C. Sites B and C both have the a Cisco 1720 with a BRI port (one 128K ISDN link attached) will respectively dial to Site A which has a 2620 router with two BRI ports as required.

Site A:

Loopback0 - 10.10.68.1

E0/0 - 10.10.69.1

Bri0/0 - no ip address

Bri0/1 - no ip address

L1--> RouterA(config)#username RouterB password 0 ciscoisdn

L2--> RouterA(config)#username RouterC password 0 ciscoisdn

L3--> RouterA(config)#int bri0/0

L4--> RouterA(config-if)#dialer pool-member 1

L5--> RouterA(config-if)#int dialer1

L6--> RouterA(config-if)#dialer pool 1

L7--> RouterA(config)#int bri0/1

L8--> RouterA(config-if)#dialer pool-member 2

L9--> RouterA(config-if)#int dialer2

L10--> RouterA(config-if)#dialer pool 2

.

.

.

L11--> RouterA(config)#ip route 10.10.18.1 255.255.255.255 dialer1

L12--> RouterA(config)#ip route 10.10.23.1 255.255.255.255 dialer2

Q1. Are L1 & L2 necessary for RouterB and RouterC to dial in (Using PPP authentication) ?

Q2. Are L11 & L12 routing correctly ?

Site B:

Loopback0 - 10.10.18.1

E0/0 - 10.10.19.1

Bri0/0 - no ip address

L1--> RouterB(config)#username RouterA password 0 ciscoisdn

L2--> RouterB(config)#int bri0/0

L3--> RouterB(config-if)#dialer pool-member 1

L4--> RouterB(config-if)#int dialer1

L5--> RouterB(config-if)#dialer pool 1

.

.

.

L6--> RouterB(config)#ip route 10.10.68.1 255.255.255.255 dialer1

Q1. Is L6 routing correctly ?

Site C:

Loopback0 - 10.10.23.1

E0/0 - 10.10.24.1

Bri0/0 - no ip address

L1--> RouterB(config)#username RouterA password 0 ciscoisdn

L2--> RouterC(config)#int bri0/0

L3--> RouterC(config-if)#dialer pool-member 1

L4--> RouterC(config-if)#int dialer1

L5--> RouterC(config-if)#dialer pool 1

.

.

.

L6--> RouterC(config)#ip route 10.10.68.1 255.255.255.255 dialer1

Q1.Is L6 routing correctly ?

Please help out.

[thisisshanky]

I assume, your bri interfaces, are using ip unnumbered command, utilising the ip address of the loopback interface on the BRI interface.

On all routers, there should be a default route, pointing to the BRI interface or the dialer interface.

For example on Site C

ip route 0.0.0.0 0.0.0.0 dialer 1

ip route 10.10.68.1 255.255.255.255 dialer 1

This should help!

[mljohnson]

First of all, you likely don't need to use Dialer Profiles at the remotes; it's more complex than is necessary. So a remote config like this would be fine:

username RouterA password 0 ciscoisdn

!

int Loopback0

ip address 10.10.23.1 255.255.255.0

!

int Bri0/0

ip unn loop 0

encap ppp

dialer map ip 10.10.68.1 name RouterA 1234

dialer-group 1

ppp multlink

ppp authen chap callin

dialer load threshold X

!

dialer-list 1 .........

!

ip route 0.0.0.0 0.0.0.0 bri 0/0 10.10.68.1

As for RouterA, same thing; you don't need Dialer Profiles really. You could have a config like this:

username RouterB password 0 ciscoisdn

username RouterC password 0 ciscoisdn

!

int Loopback0

ip addr 10.10.68.1 255.255.255.0

!

int Bri0/0

no ip address

dialer rotary 1

!

int Bri0/1

no ip address

dialer rotary 1

!

int dialer1

ip unn loop 0

encap ppp

ppp authen chap callin

ppp multilink

dialer-group 1

!

dialer-list 1 .....

!

ip route 10.10.24.0 255.255.255.0 10.10.23.1

ip route 10.10.19.0 255.255.255.0 10.10.18.1

See if that helps simplify things.

[fkseow]

Hi, for your "dialer rotary 1" in the RouterA config, what does it mean ?

Under what circumstances that I need to have "dialer profile" and what circumstances I don't need it ?

Please help out.

Thank out.

[tepatel]

Dialer profile is user specific..means every user have a specific dialer interface where you can use the different settings like, pap/chap, idle-timeout, authentication methods etc..

While Rotary-groups are more lagacy DDR..where all the users share the same config under one interface..

Pl. visit following urls for more

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/dialts_c/dtsprt5/dcdhwddr.htm#xtocid294654

http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/113ed_cr/dial_c/dcprt4/dcdiprof.htm

[fkseow]

Thank you very much on your guide.

Thank you.

[mljohnson]

When you have multiple interfaces that will be receiving or placing the same calls, then it's easiest (from the configuration perspective) to configure a rotary group, and assign each of the physical interfaces to the rotary-group - thus they will inherit the config of the rotary-group interface. This is what "dialer rotary 1" does, it associates the physical interface with "Dialer 1".

Dialer Profiles are really only needed when you have per-user requirements; ie, the users which are dialing in or to which you are dialing out to have unique interface configuration parameters. That does not look to be the case for you.

[fkseow]

Hi Sir, I had tried on the config you suggested above with "ISDN switch-type basic-net3", but from my RouterB and RouterC, when I ping to RouterA loopback address, they called to RouterA but failed.

Over RouterB and RouterC, I used commands;

sh isdn act - show nothing

sh isdn status - Layer 2 - Active

sh isdn his - out 7188223 Failed

.

.

.

Please help out.

[tepatel]

we need to see the following debug for a callout

debug isdn q931

debug ppp negotiation

debug ppp authentication

[mljohnson]

You need to have a look at the following to figure out what is wrong:

debug isdn q931

debug dialer

debug ppp neg

[tepatel]

The config looks good at this point..always it needs a whole config to verify the connectivity..All the questions answers to "YES"..Pl. visit following url for more config and troubleshooting tips

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