Unable to connect to console of switches

Unanswered Question
Nov 24th, 2008

Guys,

I am having trouble connecting to the console of several of my switches.

I have troubleshooted as best as I can. The console cable I am using does work using the same cable, laptop and configuration on the laptop on two other switches.

I have tried setting the baud rate, speed, stopbits, flowcontrol, etc as it suggests in all manuals but still no luck.

On one of the switches when I connect to the console a series of 'y's and '$' appear on the other nothing appears. If I then come back to another switch it works no problem.

Any ideas what can cause this?

Thanks

Darren

I have this problem too.
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Richard Burts Mon, 11/24/2008 - 20:10

Darren

When you describe some symptoms as "a series of 'y's and '$' appear" it suggests that the issue may be that the console port on these switches is operating at a speed different form the default 9600. I would suggest that you try the different console speeds, starting at the lowest 1200, and working you way up through the speeds of 2400, 4800, etc. Be aware that with some terminal emulators (especially with Hyperterm) that you need to stop and start the emulator session for it to recognize the change in speed.

Give it a try, using the various possible speed settings and let us know if one of them works.

HTH

Rick

darren-carr Mon, 11/24/2008 - 20:20

Hi Rick,

I have tried lowering the speed of the port I am using to connect. Here is the output of 'sh line console 0' on one of the offending switches

SW010#sh line console 0

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

* 0 CTY - - - - - 0 0 109/23853095 -

Line 0, Location: "", Type: ""

Length: 24 lines, Width: 80 columns

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

Status: PSI Enabled, Ready, Active, 0x40000

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

never never none not set

Idle Session Disconnect Warning

never

Login-sequence User Response

00:00:30

Autoselect Initial Wait

not set

Modem type is unknown.

Session limit is not set.

Time since activation: 1w2d

Editing is enabled.

History is enabled, history size is 50.

DNS resolution in show commands is enabled

Full user help is enabled

Allowed input transports are none.

Allowed output transports are none.

Preferred transport is none.

No output characters are padded

No special data dispatching characters

It all looks pretty standard to me?

Regards

Darren

darren-carr Mon, 11/24/2008 - 21:06

Also when I attempt to enter the 'login' command at line console 0 it asks me to specify an authentication the choice is 'default' or 'word'

Not sure if this is causing the problem.

We use AAA on our switches to authenticate users to our RADIUS server when they connect via SSH

Regards

Darren

darren-carr Mon, 11/24/2008 - 22:20

Lastly, you can see from the log I have never connected to the console successfully

SW002#sh line

011758: Nov 25 17:19:13.164: %SYS-5-CONFIG_I: Configured from console by darrenc on vty4 (192.168.2.42)

SW002#sh line

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

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

1 VTY - - - - - 8 0 0/0 -

2 VTY - - - - - 37 0 0/0 -

3 VTY - - - - - 50 0 0/0 -

4 VTY - - - - - 16 0 0/0 -

* 5 VTY - - - - - 11 0 0/0 -

6 VTY - - - - - 0 0 0/0 -

7 VTY - - - - - 0 0 0/0 -

8 VTY - - - - - 0 0 0/0 -

9 VTY - - - - - 0 0 0/0 -

10 VTY - - - - - 0 0 0/0 -

11 VTY - - - - - 0 0 0/0 -

12 VTY - - - - - 0 0 0/0 -

13 VTY - - - - - 0 0 0/0 -

14 VTY - - - - - 0 0 0/0 -

15 VTY - - - - - 0 0 0/0 -

16 VTY - - - - - 0 0 0/0 -

SW002#sh line console 0

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

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

Line 0, Location: "", Type: ""

Length: 24 lines, Width: 80 columns

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

Status: Ready, 0x40000

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

00:10:00 never none not set

Idle Session Disconnect Warning

never

Login-sequence User Response

00:00:30

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 20.

DNS resolution in show commands is enabled

Full user help is enabled

Allowed input transports are none.

Allowed output transports are none.

Preferred transport is none.

No output characters are padded

No special data dispatching characters

darren-carr Mon, 11/24/2008 - 22:41

Guys,

The issue is occurring on both 3560Es that I have deployed in the business. I am able to successfully connect using the same procedure/cables/etc to switches in the same cabinets (2960G).

Could this be an IOS issue???

When I connect to the console port I receive a series of 'yyyyyyyyyyyyyyyyyyyyyyyyyyyyy' for approx 20 lines and then it stops. I cannot at this point input anything into the CLI.

I have tried modifying the speed on my client and also on the switch for the 'line console 0' line of the switch.

Not sure what else to look at??

Thanks

Darren

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