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upgrading a cisco 3750x stack IOS

Hi all

can anyone tell me the quickest and easiest way to upgrade the IOS in my stack on 4 3750x switches



Garry Cross

Load the image file onto the internal flash or a usb flash (if you have physical access).

If you use the .tar file, then lookup the archive command to upgrade the switch.

There are several options to pay heed to.

I usually do the noboot option and upgrade the code during during the day.

Do the command and go on with your other business.

Check on it every once in a while. If you do it via telnet it may appear that nothing is happening for lengthy periods.

Same goes for console. You can't use the console or telnet session during the upgrade process.

You can kick off a second telnet if your inclined to do so.

Then reload the switch when you can do so at a time of least impact.

Leo Laohoo
VIP Community Legend

Hi Carl,

1.  Copy the TAR IOS to your TFTP server. 

2.  Make sure you have access to the TFTP server (from the switch).

NOTE:  There are two methods of doing this.  One is via Ethernet and the other is via USB.  I'll discuss USB later.

3.  Jump into your stack and run this command:  archive download-sw /destination 1 /dest 2 /dest 3 /dest 4 tftp:///IOS_filename.tar

If you have a USB stick:

1.  Format the USB stick with FAT16;

2.  Copy the IOS into the stick;

3.  Insert to the Master of the 3750X USB port;

4.  Command:   archive download-sw /destination 1 /dest 2 /dest 3 /dest 4 usbflash0://IOS_filename.tar


when you say the below


3.  Jump into your stack and run this command:  archive download-sw /destination 1 /dest 2 /dest 3 /dest 4 tftp:///IOS_filename.tar"

is that the actual command? would I type /dest 2/dest 3 etc ?

it would it be flash1: etc ?


It means "destination 1".

If you have four switches in a stack then you use "/destination 1 /destination 2 /destination 3 /destination 4".

The command that I have posted tells the switch to "unpack the tar file to the following switches in a stack.  they are switch 1, switch 2, switch 3 and switch 4"

what happens once they have downloaded ?

do we need to issue the boot system flash command or will it automatically do this ?

You can do either.

If you want the stack to automatically reload after the software has been installed then add "/reload" to the command. 

Hello Leo where is this USB port located on the 3750X series switches. 

The USB port is located at the back, above the stacking ports.

Tarunkumar Vyas