Use the installadm delete-client command to disassociate the macaddr client from its install service.
installadm delete-client -e mac-addr
The following command deletes the client with MAC address 00:14:4f:a7:65:70. You do not need to specify the service name because a client can be associated with only one install service.
# installadm delete-client -e 00:14:4f:a7:65:70