Summary

  Subject:

Cisco Catalyst IOS Upgrade Process

   Updated:

2024-05-05

   Author:

Tim Hammond ([email protected])

Leland Petitjean ([email protected])

   Operating Systems:

universalk9-mz.122-55.EX3

universalk9-mz.152-2.e10

   Background:

The purpose of this walk through is to demonstrate how to upgrade a Cisco Catalyst's IOS operating systems firmware to a new version.

In this example, we are upgrading a Cisco Catalyst WS-C3560CG-8PC-S switch. This is a great little switch that Tim uses at his desk. The switch has (8) PoE 10/100/1000Mbps ports and (2) 1000Mbps SFP ports.

  

Table of Contents

Prework

It is assumed that you have a active Cisco Support contract in place to cover your equipment.

To get the latest IOS version, go to: https://software.cisco.com/download/home. Login and then browse to your specific switch model. Then download the latest or your desired IOS version.

Move the *.bin file to your TFTP server. Check out our Windows - Setup a TFTP Server article.

Update Process

Create backup config

Before we get to ahead of ourselves, it is a good idea to create a backup of the startup config for the switch before we make any changes. To do this, use a console cable or SSH into the switch, then run the following command:

copy start tftp://192.168.1.50/switchName.cfg

Firmware Copy process

Engineers or Sys Admins like to leave an old copy of a IOS firmware on the switch's flash storage. Use the following command to see what is currently stored on the flash.

dir

If there is an old version of IOS or a file that you would like to delete before you copy files over, use the following command. To remove the annoying confirmation, use: /f to force the delete and use /r to make it recursive delete. This is helpful for directories that you would like to remove.

del /f /r flash:c3560c405ex-universalk9-mz.12x-xx.xxx.bin

Alright, let's copy the bits over to the switch. The format for the command is: copy source destination flash:. Type this from the console or SSH session on the switch.

copy tftp://192.168.1.50/cat3560/c3560c405ex-universalk9-mz.152-2.e10.bin flash:

After the file has been copied, please verify the checksum. The original checksum hash can be found on Cisco's website where you downloaded the firmware from.

verify /md5 flash:c3560c405ex-universalk9-mz.152-2.e10.bin

Apply Firmware

Take note of the current version using this command.

show ver

Take note of the path of the current IOS version.

show boot

Enter configure terminal mode then disable the current IOS from loading at boot. Specify the new IOS version that you want to load at the next boot. You will need to enter the file path in the commands.

config t no boot system flash:c3560c405ex-universalk9-mz.122-55.EX3.bin boot system flash:c3560c405ex-universalk9-mz.152-2.e10.bin

Exit the configure terminal mode then use the shortcut wr to copy the running-config to the startup-config.

exit wr

Are you ready for this? How exciting! Use the reload command to reboot the switch. When you hit y on your keyboard, the system will reboot. It can take a few seconds for the screen to actually update though.

reload

Cleanup

To validate our work, use the show version and show boot commands to verify you are now using the new IOS version and that the path to the file is correct.

show ver show boot

As previously stated, some engineers prefer to keep the previous IOS version on the switch in case they have to role back for whatever reason. So this step is at your discretion. Generally speaking, we opt to leave the old IOS version on the switch for a few weeks then we remove it (if we remember).

dir del /f /r flash:c3560c405ex-universalk9-mz.122-55.EX3.bin

References