Digital modem dialout using BRI on 3640

[desmckee]

Im trying to set up a 3640 router with a 4B S/T and digital modem card as an out of band management solution. A number of our routers have US Robotics 56k modems connected to their aux ports, and I would like to have a central OOB router to dial them. Most Cisco configs appear to deal with dial in, and the ones on dial out use dialers, ip addresses etc. All I want to do is reverse telnet to the modem in question, and ‘manually’ dial a PSTN number, but I cannot seem to find a way to ‘bind’ the async Ifs / lines to use the BRI.

Any ideas?

Cheers,

Des

[makchitale]

If you are going to reverse telnet into a modem & dial out using ATDT, we do not need to configuring asyn interfaces. NOTE, this is an exec session, if we had to do ppp then we will need the async interfaces.

Under the line all that we need is "transport in all".

The modem call will go out the BRI in a descending order by default (say bri 1/3 (both channels) then bri1/2, bri1/1, bri1/0)...we can alter this by CLI if need be))

We need to be sure the BRI is configured correctly & looks good in "sh isdn status"

Thanks, Mak

[desmckee]

SOrry, i need a bit more information than that. BRI config looks ok to me (basic, but if you say no PPP needed then its just and sh isdn stat is fine)

!

interface BRI1/3

no ip address

no ip directed-broadcast

isdn switch-type basic-net3

isdn incoming-voice modem

no cdp enable

!

line 97

modem InOut

transport input all

transport output pad v120 telnet rlogin

!

If i turn on modem, isdn q931 debugs and telnet to the modem, then try and dial, all i get is DS1 network inaccessible? I dont see the BRI do anything.

5d20h: Modem 3/0 Mica: configured for Originate mode, with Null signaling, 0x1 tone detection.

5d20h: Modem 3/0 Mica: received dialstring 123456

5d20h: Modem 3/0 Mica: in modem state CALL_SETUP

5d20h: Modem 3/0 Mica: in modem state TERMINATING

5d20h: Modem 3/0 Mica: in modem state IDLE

5d20h: Modem 3/0 Mica: DISCONNECT after 00:00:00, due to reason (0x7F05) DS1 network inaccessible (busy).

Cheers,

Des

[makchitale]

My bad, we need to add "modem dialout interface BRI x/y". NOTE: we can add multiple commands under the same line pointing to different BRI interfaces (see config below) & do not really need any other configs on the BRI interfaces.

interface BRI4/0

no ip address

isdn switch-type basic-5ess

!

interface BRI4/1

no ip address

isdn switch-type basic-5ess

line 33

modem InOut

modem dialout interface BRI 4/0

modem dialout interface BRI 4/1

transport input all

c3745#sh isdn sta

Global ISDN Switchtype = basic-5ess

ISDN BRI4/0 interface

dsl 32, interface ISDN Switchtype = basic-5ess

Layer 1 Status:

ACTIVE

Layer 2 Status:

TEI = 64, Ces = 1, SAPI = 0, State = MULTIPLE_FRAME_ESTABLISHED

Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 32 CCBs = 0

The Free Channel Mask: 0x80000003

c3745#telnet 1.1.1.1 2033

Trying 1.1.1.1, 2033 ... Open

atdt914085268470

*Sep 10 15:15:08.531: Modem 1/0 CSM: Called Number Rcvd = T914085268470

*Sep 10 15:15:08.531: Modem 1/0 CSM: Dropped character T

*Sep 10 15:15:08.531: Modem 1/0 CSM: Dial String to be processed (914085268470)

*Sep 10 15:15:08.531: Modem 1/0 CSM: End of Dial String

*Sep 10 15:15:08.531: Modem 1/0 CSM: (CSM_PROC_IDLE)<--MODEM_DIAL_OUT

*Sep 10 15:15:08.531: Modem 1/0 Mica: configured for Originate mode, with Null signaling, 0x1 tone detection.

*Sep 10 15:15:08.531: Modem 1/0 Mica: received dialstring T914085268470

*Sep 10 15:15:08.531: ISDN BR4/0 Q931: TX -> SETUP pd = 8 callref = 0x06

Bearer Capability i = 0x8090A2

Standard = CCITT

Transer Capability = Speech

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0x83

Keypad Facility i = '914085268470'

Locking Shift to Codeset 6

Codeset 6 IE 0x23 i = 0x01

*Sep 10 15:15:08.643: ISDN BR4/0 Q931: RX <- CALL_PROC pd = 8 callref = 0x86

Channel ID i = 0x89

Thanks, Mak

[desmckee]

Thanks Mak, but i cant find an IOS that supports the modem dialout BRI command? Cant find it on command lookup either... Its a 3640 were tryingt on, have tried right up through 12.2 Enterprise feature set with no luck. Is it a special release?

Thanks a lot,

Des