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3850 System LED blinking fast - not getting past POST?

SuperDragon
Level 1
Level 1

I pulled a brand new Cisco 3850 Switch out of the box yesterday.  Following the Quick Start Guide, I put in the power module, powered it on, and waited for it to complete POST.  Then, I plugged in an Ethernet cable between a laptop and the switch on a port in the front, and went to the web interface at https://10.0.0.1.  I got to the Express Setup, and attempted to change the IP address of the switch to an IP on my LAN, along with other options.  When clicking submit, it didn't appear to take.  Upon refreshing in the Express Setup, the IP config was blank, so I once again configured it.  This time clicking submit brought up a message that it was changing the IP address.  I waited for it to finish, and when it looked done, I powered the switch off and took it to a different room to hook it up to the LAN for further configuration.

When plugging in the power at that point, the switch starts through the normal light process (System LED blinks green slowly), and then eventually the System LED blinks green very fast and never stops.  It doesn't get to the point of having the system loaded and ready to log into.  There's no amber lights, just the System LED flashing green fast.  On the back, the Power module and all bay lights are green, and the Console light is green, but the Management port light is off.

I've tried using the reset button on the back of the switch two different times to reset it to default configuration, thinking I hosed it somehow, but it never goes past the fast blinking System LED.

What can I try from here?

5 Replies 5

Reza Sharifi
Hall of Fame
Hall of Fame

Try consoling to the switch.  Take the blue console cable that comes with the switch and plug one side to the switch and the other side to your laptop and then turn on the switch and see if it boots all the way.  You need to install Putty software  (it is free) to use the console port.

HTH

I'll have to see if I have another Console cable around here, as this switch did not come with one (the guide lists both an RJ45 and a USB Console cable as "Optional" parts).

I have Putty, so I will try that.  Thanks.

Usually, the blue RJ45 to DB9 cable comes in the box, but the USB has to purchased separately.

This one did not come with a blue console cable either.  Luckily, I had one.  I was able to go in through the console cable, reset the switch and watch.  It was telling me that the flash image was not found.  I found this document and used the workaround to correct the issue:

http://www.cisco.com/en/US/customer/ts/fn/636/fn63641.html

Reza Sharifi wrote:

Usually, the blue RJ45 to DB9 cable comes in the box, but the USB has to purchased separately.

Cisco is not shipping console cables with switches  Probably thye assume people will use a mini USB cable for USB console.

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