3750 Stack - IOS Upgrade

[malcolmpdwilson]

Hello,

I want to upgrade the IOS on my stacked pair of 3750s. There is not enough flash to install the new IOS alongside the old one. Can I do this:

1. delete old IOS from flash1:

2. copy new IOS to flash1:

3. set system boot variable to use flash1:

4. reload and have both switches come up with the new IOS

5. check everything is OK

6. delete the old IOS from flash2:

7. copy new IOS to flash2:

I understand why it is not advisable to have mismatched IOS on the switches with a stack permanently. But is it OK for doing the upgrade, so that in case of problems I can change back to the old IOS more quickly?

I haven't found any documentation which explicitly states that it is possible to do this, and I don't have a way to test it myself, so I am looking forward to hearing an authoritative answer!

Regards,

Malcolm

[sdheer · Accepted solution]

Hi Malcolm ,

In order for switches in a stack to come up with the new image ,we need to have the image in the flash of all the member switches.

Therefore if you have the image in just one flash and not in other as you mentioned and you relaod with the boot variable set the secind switch will not come up with the new image.

Please refer to the follwoing doc ,which will guide you to do the needful.

http://www.cisco.com/en/US/products/hw/switches/ps5023/products_configuration_example09186a00804799d7.shtml

http://www.cisco.com/en/US/products/hw/switches/ps5023/products_configuration_example09186a00807811ad.shtml

Hopt that helps.

Regards,

Swati

Please rate if you find content useful

[Latchum Naidu · Accepted solution]

Hi Malcolm,

What you have mentioned the steps looks fine, you have to do one by one upgrade for all stack switches simultaneously.

Because first of all you have to make sure all the switches which are in stack have same IOS.

Regards,
Naidu.

[malcolmpdwilson]

Thanks very much for your replies.

Each switch boots only from a locally saved IOS, and cannot boot using the IOS stored on another switch.

Regards,

Malcolm

[hobbe]

Since you do not have place for the different IOS images I presume that you are using the webinterface ?

if not then I would start with only copying the bin file and install that since it is a lot smaller.

that should enable you to have both IOS images inplace at the same time ?

just a thought that might help you..

Good luck

[malcolmpdwilson]

Hi,

Thanks for the tip, it's a good idea, but even old and new .bin files don't fit together when there's only 16Mb flash!

As for the web interface, I've never used it. People where I work are called bad names when they are seen using GUIs if there's a CLI available!

Regards,

Malcolm