Here’s a silly little issue I hit this afternoon – mostly a case of "administrator error" but a time waster nevertheless.
To recap, there was a big change to Web Tier administration in 12.1.2 in that OHS is controlled with what’s now called the "WebLogic Management Framework" – in short this means OHS instance configuration is handled via WLST and lifecycle (start/stop etc) by Node Manager (i.e. OPMN has gone). You have a choice of either co-locating OHS in your existing WebLogic domain (diagrams from the Oracle Documentation):
Otherwise you can have OHS on its own: Read the complete article here.
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