1. Delete the faulty node A on the OMU portal of the master domain node or master node of the upper-level domain.
2. Register node A again.
a) If node A is a slave domain node - switch node A to the single-node system and then back to the slave domain node and register node A with the master domain node again.
b) If node A is a lower-level domain node - clear the upper-level NE IP address of node A and register node A with the master node of the upper-level domain.
