Jerome,

I understand that. The documentation from Cisco says I have to save my config while my controller is still using 4.1.170. Then upgrade to 4.2.130. It said to back the config up before doing so as I will lose the current config. My question is what do I save the 4.1 config file as .txt, .xml, .make something up??? I'm presuming that once I upload that saved config back to the controller it will convert it to the newer 4.2 .xml format. Am I correct in assuming that?

Jerome,

This is from the 4.2.112.0 release notes:

In controller software 4.2, the controller's bootup configuration file is stored in an Extensible Markup

Language (XML) format rather than in binary format. Therefore, you cannot download a binary

configuration file onto a controller running software release 4.2. However, when you upgrade a

controller from a previous software release to 4.2, the configuration file is migrated and converted to

XML.

This conflicts with what Cisco states earlier in their documentation. I thought when you upgrade it wipes everything and you loser your current config? After reading this section I gather that I only lose the running config and that it will upgrade the config stored in NVRAM? That all makes a lot more sense than what they say earlier in the guide. Once I do the upgrade I can't impor the old config due to it being in the wrong format.

So in closing this mess my take is that I just need to upload the new software image to the controller. It will load the new software version and then convert the existing config in NVRAM into the new .xml format? Yes?

In short, you will be fine upgrading, but when you downgrade, you will loose everything. I have just tested it with a wlc running 3 code and upgrading it to 4.2.130. Kept the configuration.

Yes!

To be clearer:

- You have a controller with 4.1 code, you save your config as a safety, it's a binary file, name it the way you want (I use .cfg, but there is no boligation, the file extension will not determine the file format, it will be proprietary binary format anyway).

- You upgrade the config to 4.2. The config onboard the controller is maintained.

- You suddenly change your mind and want to downgrade to 4.1 (not using the 4.1 backup image still present in your controller, but by downloading a new 4.1 image). Your config is wipped but you can reimport the config you wisely saved before moving to 4.2.

Does that make more sense?

hth

J