execute and I get the following
./rman target sys/ehealth@%NH_DB_CONNECT_STRING%
Recovery Manager: Release 11.2.0.4.0 - Production on Fri Aug 31 11:49:30 2018
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00554: initialization of internal recovery manager package failed
RMAN-04005: error from target database:
ORA-12154: TNS:could not resolve the connect identifier specified