i have upgraded all of my 900 ap’s to 9.0 but i have some sm’s with less than ideal links(installed at customers own risk) since i have never atempted an upgrade of sm’s in this manner i’m a bit conserned about what will happen if they start to update and lose connection during the upgrade.
The upgrade process happens in two steps: transfer the new firmware to the radio, and burn the new firmware. Losing link will not affect it - if the transfer fails you can just try again. I haven’t tried with a power loss during the burn part of an upgrade, but I suspect that will brick one quite well.
The canopy team has been very thoughtful and careful about implementing the upgrade process so that it is virtually impossible to “brick” a device during and upgrade. At the Animal Farm conference in Salt Lake this last January they discussed this and from my memory of the discussion the canopy units keep a full copy of the currently installed firmware and a completely separate copy of the new upgrade. Until the unit is able to successfully boot from the new firmware image it will hold onto the old one to revert back to if something should fail, there by preventing a “bricked” unit.
They did this because they knew that at times there may be wireless conditions that prevent an upgrade from being successful. By retaining 2 copies until successful they prevent anything bad from happening.
upgrade at will…