how do i create an update for an appliance?

hi..

i know there's a way to create an update using the update manager. but i'm not sure how it works.

currently we need to things updated.

1. update the java server se (we are now doing it via a custom page we created ourselves)

2. update back end and boot up scriupts

3. update custom management pages without the need to re-deploy the ova

we would like the option that will not require an external connection to an outside internet server but allow the customer to update said patches using just an upload file feature.

can this be done?

how does the update package actually works?