Application interference
Sometimes an application or an application environment might interfere with the proper functioning of PowerHA® SystemMirror®. An application might run properly on both the primary and standby nodes. However, when PowerHA SystemMirror is started, a conflict with the application or environment could arise that prevents PowerHA SystemMirror from functioning successfully.
Products manipulating network routes
Additionally, products that manipulate network routes can keep PowerHA SystemMirror from functioning as it was designed. These products can find a secondary path through a network that has had an initial failure. This routing might prevent PowerHA SystemMirror from properly diagnosing a failure and taking appropriate recovery actions.