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Serial Console connection problems

Monorail_Matt
Level 1
Level 1

Hi, I'm working with a Catalyst 3650, using PuTTY as the terminal interface.  I installed a new ios image on friday due to an accidental deletion of the original image from flash (it's now monday). Connection via console cable was working fine on friday night, even after power cycling the device, however come today I am unableto get the device to respond via serial connection. The switch looks to be working fine, is passing data just fine. 

I have tried multiple baud rates from 1200 up to 117000 based on searches through the cisco forums. 

I have tested the serial cable connection and PuTTY using an HP switch set to 38,400, 8, 1, N and it works just fine. 

 

I am unsure what has happened to the cisco switch. If I hold the mode button and interrupt the boot, it still doesn't show anything in putty, not even the logs as it starts. 

 

The switch sat unplugged from power over the weekend but I wouldn't expected that to change anything. After reloading the new ios (Denali) the switch was power cycled and also "reboot" & "reload" using the CLI. The only difference is it was sitting for 2 days without the power plugged in. 

 

I am lost.

1 Accepted Solution

Accepted Solutions

Don't take it wrong, there are 2 ports 1 is MGMT and 1 for Console. if you already tried the console, try with a different device PC if you can (no harm trying?

 

If nothing appears, if you have a contract raise a TAC case for RMA. (nothing much you can do if do not see anything on the console)

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5 Replies 5

balaji.bandi
Hall of Fame
Hall of Fame

As per the description - something failed hardware level.

 

But you mentioned that  switch able to pass the data traffic, have you tried SSH to the device?

 

Another Option: Pull the Power lead, give some time switch go down completely for 5min, connect the working console cable (try to use a different terminal - if you can) - putty still good. or download another version online on a different folder.

 

switch on the device - do nothing just watch the console boot process? ( first, do you see console output ?) what LED in front start blinking while switching ON?

 

 

 

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Hi Balaji, 

 

I do not have an ip address set yet, as I had just re-flashed the ios on friday and hadn't done any additional setup yet, which is why I'm wondering if someone has gone wrong with some of the software. Switch hasn't been moved since Friday either. 

 

Upon startup, SYST blinks, eventually all status lights light up and the fans crank up to max again (SYST is still blinking), then i get STAT, SYST & ACTV lit up in solid green. And from there the switch seems to function as normal (apart from no console output). Putty responds as though it's attached to something, in the way it allows me to type text where connecting to a blank com port doesn't allow me to enter text. Nothing displays from the switch however. 

Don't take it wrong, there are 2 ports 1 is MGMT and 1 for Console. if you already tried the console, try with a different device PC if you can (no harm trying?

 

If nothing appears, if you have a contract raise a TAC case for RMA. (nothing much you can do if do not see anything on the console)

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Monorail_Matt
Level 1
Level 1

I wish I had more to add than this , but after power cycling 3 times in a row, holding mode to stop regular boot then power cycling and letting it start up normally, the CLI started working again. This was after again connecting it to an HPE switch to verify my COM port and cable were working fine. I then plugged the cable back into the Catalyst, put baud back to 9600 (HPE uses 38400 baud) and rebooted it and VOILA! it was working again. I had also previously rebooted my PC several times too. 

I am going to clean out the console port just incase there is dirt causing the issue. 

 

Thank you very much Balaji for responding so quickly to my post. Much appreciated.  

Thats nice to hear, your hardwork paid off...good and glad all well now.

 

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