Dial-up Access to Cisco Router

Posted on 2004-08-11
Last Modified: 2010-08-05
Need to configure Cisco 2651 (has 8 internal modems) to accept incoming calls.  Then give caller remote admin access to domain controller.  Any ideas?

Question by:adraffin2004
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LVL 13

Expert Comment

ID: 11781228
Work from this example config:

Adapt it to your environment and see how you go. Once the user is connected vial dial-up and has a TCP/IP connection, then they can connect using the normal remote desktop software.

Any question, ask back here.

Author Comment

ID: 11783526
Thanks for the article.  I will try it now and let you know the status.


Author Comment

ID: 11784244
The main difference I see in the article's config is that the modem port is assoc with serial port 3/7.

I am not using serial ports.  Here's what "show line" produces:

gai-rtterminal#show line
   Tty Typ     Tx/Rx    A Modem  Roty AccO AccI   Uses   Noise  Overruns   Int
     0 CTY              -    -      -    -    -      0       0     0/0       -  Ready
    33 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    34 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    35 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    36 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    37 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    38 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    39 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    40 TTY              - inout     -    -    -      0       0     0/0       -  Ready
    65 AUX   9600/9600  -    -      -    -    -      0       0     0/0  -  Ready
*   66 VTY              -    -      -    -    -      8       0     0/0       -  Ready
    67 VTY              -    -      -    -    -      0       0     0/0       -  Idle
    68 VTY              -    -      -    -    -      0       0     0/0       -  Idle
    69 VTY              -    -      -    -    -      0       0     0/0       -  Idle
    70 VTY              -    -      -    -    -      0       0     0/0       -  Idle

Line(s) not in async mode -or- with no hardware support:
1-32, 41-64


I am assuming I must use line 40 because I have a phone line plugged into modem slot #1.

Here's the output for "show line 40":
gai-rtterminal#show line 40
   Tty Typ     Tx/Rx    A Modem  Roty AccO AccI   Uses   Noise  Overruns   Int
    40 TTY              - inout     -    -    -      0       0     0/0       -

Line 40, Location: "", Type: ""
Length: 24 lines, Width: 80 columns
Status: Ready, No Exit Banner
Capabilities: Hangup on Last Close, Integrated Modem
Modem state: Ready
modem(slot/port):1/7, csm_state:IDLE_STATE,
bchan_num:-1 csm_status(0): CSM_STATUS_UNLOCKED

Modem hardware state: CTS noDSR  noDTR RTS
Special Chars: Escape  Hold  Stop  Start  Disconnect  Activation
                         ^^x    none   -     -         none
Timeouts:      Idle EXEC    Idle Session   Modem Answer  Session   Dispatch
                      00:10:00        never                                    none     not set
                            Idle Session Disconnect Warning
                            Login-sequence User Response
                            Autoselect Initial Wait
                              not set
Modem type is unknown.
Session limit is not set.
Time since activation: never
Editing is enabled.
History is enabled, history size is 10.
DNS resolution in show commands is enabled
Full user help is disabled
Allowed transports are pad v120 telnet rlogin.  Preferred is telnet.
No output characters are padded
No special data dispatching characters

If I dial the modem's phone number it just rings.. never answers.

LVL 13

Accepted Solution

td_miles earned 125 total points
ID: 11788979
Sorry about that, hasty post, just as I was leaving the office.

OK, I'm going to assume that you have an NM-8AM module to provide the 8 internal modems (if this isn't correct, please let me know what it is).

>> I am assuming I must use line 40 because I have a phone line plugged into modem slot #1.
No, if you have the line plugged into modem slot#1, you should be using line 33 (the first in the group).

The router reserves 32 line numbers for each network slot, in order. This tells me that you have the modem module plugged into slot 1 (the second slot, after slot 0). Slot 0 gets line 1-32, Slot 1 gets line 33-64. You only have a 8 line card, so only 33-40 are used, but this is why your AUX is line 65 and the VTY's after this. For a better explanation, have a read here:
(It is for 3600 routers, but is still relevant).

For an idea of how lines, async & group async interfaces all fit together, have a look at Figure 15 on this page:
Essentially each physical line interface gets its own async interface. You can then group the async interfaces together, so that you can apply a single configuration over all (or only some) of the interfaces.

Now, again assuming NM-8AM, this page will show you how to configure it for dial-in:

Author Comment

ID: 11794034
The article was very helpful and I now have dial-in remote access to my servers from home.  Thanks for your help.

My next goal is to have dial-up access via DSL or Cable modem from home.


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