Not able to create containers with error message- java.rmi.ConnectException: Connection refused to host

Issue

• I suddenly cannot create child containers anymore, on the same Fuses running on the same machines where previously everything was working. Both on 6.1 and 6.2 versions.
• Executing the command

container-create-child <root-container> <any-child-container>

• I always obtain this error on client console:

The following containers have failed:
        <not available>: java.rmi.ConnectException: Connection refused to host: A.B.C.D; nested exception is: 
        java.net.ConnectException: Connection timed out