The possible modes for the Primary appliance are:
The modes for the Replica are:
To establish normal HA configuration so that changes are sent from the Primary to the Replica the modes should be like this:
Primary should be in "Replicating"
Replica should be in "Replica"
When the Primary is in Replicating mode it will search for a Replica appliance to send updates to. As long as it is in this mode it will continue searching for a Replica even if it is not there.
The Replica will only receive updates from the Primary when it is in "Replica" mode. If it is in Test mode or Primary mode it will not receive updates (even if the Primary is trying to send updates to it.)
If the Replica is going to be in Primary mode for an extended period of time (more than 8 hours), then it doesn't make sense for the Primary to keep trying to send updates when it won't receive them. So in that case, we suggest that you put the Primary into Standalone mode. When the Primary is in Standalone mode it will not search for a Replica and will not send updates. If you are only changing the Replica to Primary for a short time, then you don't have to change the Primary.