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got my rack

cisco steps
Level 1
Level 1

ok I just invested on some cisco equip

here is what I have

3 x 2610

12 port 2900 xl

24 port 2900 xl

2511 access server

2501

I would like to access all the swithces and router w/ out removing the cable using the access server 2511 .. can I do that ? or I have to configure each device then see how I can connected then w/ Asynchronous Serial Interface Breakout Cable ..thanks

2 Accepted Solutions

Accepted Solutions

Hi,

If i understand you correct, you are trying to do reverse telnet from the 2511 to your devices, accordingly you'll need this configuration:

under the serial interface (If A/S):

physical-layer async

under the async line:

transport input telnet

stopbits 1

and connect the cables to the console of your devices.

Issue this command to establish a reverse Telnet connection from your 2511:

telnet x.x.x.x 2yyy or [2000+yyy]

The x.x.x.x represents the IP address of any up/up interface on the Cisco router (recommended to be a Loopback) and yyy is the line number to which you want to connect. If you have already configured the TTY line, you can issue the telnet command from anywhere on the network that can ping the x.x.x.x interface.

To disconnect, hit Ctrl-Shift-6 and then x to get back to the router prompt and then type in disconnect to close the connection.

Note: Make sure you close the connection or it will not work.

HTH, please rate if it does help,

Mohammed Mahmoud.

View solution in original post

Hi Karim,

Can you please configure the loopback interface and use it instead of the ethernet interface.

And can you please post your configuration if the problem persists.

HTH, please rate all helpful posts,

Mohammed Mahmoud.

View solution in original post

21 Replies 21

balajitvk
Level 4
Level 4

this was not clear, I think I still have to config each router separatly w/ each one have new Ip address, once that done then I can access the 2511 access server and give it the info on each router in the network..pls correct me if I am wrong .. thanks for the reply...

Hi,

If i understand you correct, you are trying to do reverse telnet from the 2511 to your devices, accordingly you'll need this configuration:

under the serial interface (If A/S):

physical-layer async

under the async line:

transport input telnet

stopbits 1

and connect the cables to the console of your devices.

Issue this command to establish a reverse Telnet connection from your 2511:

telnet x.x.x.x 2yyy or [2000+yyy]

The x.x.x.x represents the IP address of any up/up interface on the Cisco router (recommended to be a Loopback) and yyy is the line number to which you want to connect. If you have already configured the TTY line, you can issue the telnet command from anywhere on the network that can ping the x.x.x.x interface.

To disconnect, hit Ctrl-Shift-6 and then x to get back to the router prompt and then type in disconnect to close the connection.

Note: Make sure you close the connection or it will not work.

HTH, please rate if it does help,

Mohammed Mahmoud.

Mohamed thanks for the input..

I am not near my lab, but I will be later on, If i understand you correct..

I need to use the async cable that have a 8 rj 45, connect scsi to 2511 and then each ethernet cable from the same cable to eacn router.. then go to my 2511 access server and telnet to 172.1.1.1 2yyy.. what is 2yyy and how I can find it.. I am about the hit the books once I get the devices working and talking to each other .. Thanks Mo

karim

Hi Karim,

You have got it right, since the CAB-OCTAL-ASYNC cable is itself rolled, you can connect each cable directly to the console ports of devices with the RJ-45 interfaces.

After adding "transport input telnet" and "stopbits 1" under the lines, all that you have to do next is to do "show line" and then add the number to 2000 thats how you get the 2yyy number (port number) to use to reverse telnet, ex: for line 5 use 2005.

Each line corresponds to an RJ-45 cable and thus to one of your devices.

you can add an Alias for each of your devices:

ip host

ex: ip host 2611 2013 172.21.1.1

Enjoy :)

HTH, please rate if it does help,

Mohammed Mahmoud.

Mo

Thanks a lot...I think I got it, if any question will let you know, can wait to go home and play .

Hi Karim,

You are more than welcomed, and i hope you'll enjoy your lab, and please don't hesitate for any further questions.

BR,

Mohammed Mahmoud.

Hi Mo

I just tried to telnet to 2610 router from the 2511 access server but got this msg. I can see the console light green in the back flashing time to time, am I missing anything..

Thanks

R3#telnet 172.1.1.1 2008

Trying 172.1.1.1, 2008 ...

% Destination unreachable; gateway or host down

show line

*****************

Tty Typ Tx/Rx A Modem Roty AccO AccI Uses Noise Overruns

* 0 CTY - - - - - 0 0 0/0

1 TTY 9600/9600 - - - - - 0 0 0/0

2 TTY 9600/9600 - - - - - 0 0 0/0

3 TTY 9600/9600 - - - - - 0 0 0/0

4 TTY 9600/9600 - - - - - 0 0 0/0

5 TTY 9600/9600 - - - - - 0 0 0/0

6 TTY 9600/9600 - - - - - 0 0 0/0

7 TTY 9600/9600 - - - - - 0 0 0/0

* 8 TTY 9600/9600 - - - - - 0 0 41/127

shillyar
Cisco Employee
Cisco Employee

Hello,

You can do that fine just make sure your main ip address is up up or you will not be able to telnet to the console ports.

telnet 172.1.1.1 2008 172.1.1.1 need to be an up up interface and the console will cable will be on port 8. Many people just create a loop back for comservers. Then you can create an host for every console port or you can do a manual telnet to each port.

Im assuming you are using the octupus cable. The cable will be labeled with each async port #.

make sure under your lines you have "transport inpu

Thanks Steve

Hi shillyar

when you say main ip address is up up ? is this on the server or on the 2600... Thanks

Hi Karim,

All that you need is a loopback ip on your 2511 (comm-server), these 2 lines under your lines:

transport input telnet

stopbits 1

Before doing the reverse telnet, do the "show line" and make sure that there is no * beside your desired line (* means that it is in use), accordingly do a "clear line x" until the * disappears, and then try your reverse telnet.

HTH, please rate if it does help,

Mohammed Mahmoud.

Hi Mo

how are you ?

so once the 2511 is up I will type

#transport input telnet

#stopbits 1

is that what you mean ?

Thanks again , I know I am asking lot of questions for newbie .. but I am just eager to get my lab up so I can start preping for my CCNA..

Thank you all that responded

karim

Hi Karim,

No these 2 lines, must be configured under the line configuration mode, when you do sh run it should look something like this:

line 65 80

transport input all

stopbits 1

You are very welcomed, and i hope you'll enjoy your lab :)

HTH, please rate all helpful posts,

Mohammed Mahmoud.

I am so confused, I try to do it myself and was not able too.I do not want to give up . I am sure once ITS UP I can proceed but for now still no comunication b/w comm-server and 2610 router/ I did #show user all command as well as #show line 8 here is what i got

**********************************************

3#show line 8

Tty Typ Tx/Rx A Modem Roty AccO AccI Uses Noise Overruns

* 8 TTY 9600/9600 - - - - - 0 0 1/7

Line 8, Location: "", Type: ""

Length: 24 lines, Width: 80 columns

Baud rate (TX/RX) is 9600/9600, no parity, 2 stopbits, 8 databits

Status: Ready, Active

Capabilities: none

Modem state: Ready

Special Chars: Escape Hold Stop Start Disconnect Activation

^^x none - - none

Timeouts: Idle EXEC Idle Session Modem Answer Session Dispatch

0:10:00 never none not set

Session limit is not set.

Time since activation: 0:05:08

Editing is enabled.

History is enabled, history size is 10.

Full user help is disabled

Allowed transports are pad telnet rlogin. Preferred is telnet.

No output characters are padded

No special data dispatching characters

Modem hardware state: CTS* DSR* DTR RTS

**********************************************

R3#show run

Building configuration...

Current configuration:

!

version 11.0

service password-encryption

service udp-small-servers

service tcp-small-servers

!

hostname R3

!

enable secret xxx

enable password xxx

!

no ip domain-lookup

!

interface Ethernet0

ip address 172.23.23.3 255.255.255.0

shutdown

!

interface Serial0

no ip address

shutdown

no fair-queue

!

interface Serial1

no ip address

shutdown

!

ip name-server 10.10.10.10

!

line con 0

password xxx

login

line 1 16

transport input all

line aux 0

transport input all

line vty 0 3

login

line vty 4

password xxx

login

!

end

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