Note for upgrades from 2.9 to 3: We have reports of some 2.9.xx upgrades to v3 failing on upgrade on RB500 where the board becomes non-functional until Netinstall. We have not found any solution yet, it is advised to ensure physical access before upgrading.
when mikrotik says the rb500 gets non-functional what you really mean, because I have a few rb500 with the actual 3.2 and they works fine.
regards,