Before you begin the upgrade process, review the following list of changes for standalone Oracle HTTP Servers in 12c:
The installer will no longer create a separate instance directory for Oracle HTTP Server. Instance information for the standalone OHS will be stored in a new standalone domain home. For more information, see Understanding the Standalone Oracle HTTP Server Topology.
OPMN agent and opmnctl command line utility are no longer used in Oracle Fusion Middleware. Instead, system components are managed by NodeManager and WLST commands.