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I've got an 8 port BRI ISDN module on a 3640. 4 BRI ISDN interfaces are sharing the same telephone number. Is it possible to support multiple simultaneous dial-up connections with callback and how is it done? Do I need multiple dialer interfaces and pools

The telco has configured 4 S/T BRI interfaces into the same group under a single number. all of the isdn interfaces have the following config:

int bri1/0

no ip address

encap ppp

dialer pool-member 1

isdn sw basic-net3

isdn incoming-voice modem (for digital modems)

isdn send-alerting

ppp auth chap pap callin

the dialer interface

int dialer1

ip unnum eth 0/0

encap ppp

no ip split-hor

dialer pool 1

dialer idle-time 0

dialer-group 1

peer default ip address pool D...

no cdp ena

ppp callback accept

ppp auth pap chap callin

ppp multi

the first call placed is dialed back and connects okay (full ip connectivity)

the second incoming call is called back and connects (full ip connectivity) but the first call loses ip connectivity. the call is still connected, and the ip address is still in the Router. but connectivity is dead, apart from the extremely rare returned ping packet. are there any glaring omissions in this config or is it the telco's problem, their end?

  • Other Network Infrastructure Subjects

Re: I've got an 8 port BRI ISDN module on a 3640. 4 BRI ISDN int

Since you are using dialer profiles and

you have one dialer interface, you can

only have one user dial in. I think you

should remove the pool commands, and

just use a dialer-rotary group that can be

used by multiple users. The config would

otherwise be the same.