The OpenBSD Upgrade Process
An OpenBSD upgrade has three distinct phases: installing the newer versions of the operating system files, updating the local configuration, and updating obsolete add-on software packages. Each is a separate part that requires independent handling.
An upgrade requires installation media. The best upgrade media is the new release CD or an Internet mirror. You can also upgrade OpenBSD by building and installing the source code directly on the machine to be upgraded, but doing so is more difficult and risky than upgrading from the official release. Much of the information for upgrading from a network or CD applies to upgrading via source code.
OpenBSD supports upgrading only one major release at a time. You cannot ...