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NEXUS 3048TP-1GE no console after upgrade

Hi all,

I upgraded the NEXUS 3048TP-1GE to 6.0.2.U6.7. After the reboot I'm unable to access the console port. I'm connected directly with my laptop, but I can't see any output. I tried to exchange the power supplies but it didn't help.

I installed the new SW by :

install all kickstart bootflash:/n3000-uk9.6.0.2.U6.7.bin system boootflash:/n3000-uk9-kickstart.6.0.2.U6.7.bin

Any idea how can I repair the Nexus? Any help is much appreciated




Hello Pavol,

When you console , do you see LOADER prompt or anything?

Are you able to telnet or ssh to it?
Did you try to use any other consile cable?

If you are not able to ssh adn telnet and not able to console it looks like a hardware failure.

You can also try to reboot it by taking off powercable and plugin it back.


Shashank Rathee

Nothing on the console. 

I have Nexus 3048 switch. Did the n3000-uk9.6.0.2.U6.8.bin  upgrade, everything went just fine, no errors nothing. Switches posted restarting in 10 seconds and never came back. Nothing on the console. Restarting the switch does not show anything, not even a single character on the console. The fan light is orange after the upgrade. I changed it with a confirmed working fan and the light is still orange, so it is not the fan. The blue ID light on the front and back stays on all the time. Tried changing power supplies, fan, power cables. Nothing. 

Hello Ivan,

We are hitting following bug:

Nexus doesn't boot after upgrade to 6.0.2.U6.7
Nexus doesn't boot after upgrade to 6.0.2.U6.7 from release older than 6.0.2.U6.2

not known

Tested working upgrade path
5.0.3.U5.1 > 6.0.2.U6.2 > 6.0.2.U6.7

We need to run the workaround by following the above upgrade path.

Please feel free to contact me in case of any concern.


Shashank Rathee

So if it is a bug, and I am without console access, what can I do about it? The units are out of warranty? Anything we can do about it?

Unfortunately , we cant do anything , device needs to be replaced for this, then only we can run the workaround.


Shashank Rathee

What is the procedure to check if Cisco will replace it due to their bug? 

Hello Ivan,

You can try to open TAC case,  however since this device is not under warranty , TAC wont be able to replace the device.


Shashank Rathee

Hi Shashank,


I've recently run in to exactly the same issue going from 6.0.(2)U2(9Z) to 6.0.(2)U6(8).  I now have a Cisco N3K-C3048-ZM-F which is bricked.


Process was followed with "success" messages and then the "reboot" process completed, after reboot no CLI access on the rear management port.  


This unit is out of warranty and therefore a TAC case cannot be raised, can you please advise what can be done please as upgrading a unit which passed its pre-tests and then successfully upgraded surely cannot result in a unit which can't be recovered? 


I look forward to hearing from you.



Any suggestions on how to recover this unit ?  

Two months and no response, hello Cisco ?

Cisco Nexus 3000 Series platforms require a BIOS upgrade to load Release 7.0(3)I2(1) or later images. Only BIOS versions 3.x.x are compatible with Release 7.0(3)I2(1) and later releases on all Cisco Nexus 3000 Series platforms. This is taken care in the regular install all method of upgrade but it needs to be explicitly upgraded prior to the fast-reload upgrade.

In Release 6.0(2)U6(3a), an additional CLI option is introduced to upgrade only the BIOS:

switch# install all nxos bootflash:<image_name> bios

This step needs to be run from Release 6.0(2)U6(3a) and it upgrades only the BIOS image from Release 7.0(3)I2(1) image; It does not reload the switch.
During the BIOS upgrade, the system warns that the install is disruptive, but it is actually not disruptive and the device will not be reloaded. You can proceed with the BIOS upgrade.
f you have a release prior to Release 7.0(3)I2(1), upgrade to Cisco Nexus 3000 Release 6.0.2.U6(3) first. Use the install all nxos bootflash:<image_name> bios command in Release 6.0.2.U6(3) to upgrade the BIOS version to version 3.x.x. Next, fast reload from Release 6.0.2.U6(3) to Release 7.0(3)I2(1) and later releases. On fast reload to Release 7.0(3)I2(1), the new BIOS is effective.

Not sure if it was hardware failure or if I just bricked a 3048 after firmware upgrade.  This firmware upgrade process is not clear. The messages on the console and instructions are confusing and murky.  Isn't there a mechanism to stop the switch from breaking itself?  My suggestion to Cisco is to improve the documentation and put step by step instructions in plain English on what to do for each firmware upgrade. Or have system checks in place to not allow the admin to initiate an upgrade that will destroy itself.  I spent 2-3 hours reading the documentation and after firmware upgrade switch is dead, no response on console. Thanks