Setup and use PDB_OS_CREDENTIAL

Hi

Did anybody successfully setup and user PDB_OS_CREDENTIAL? I do have a test case but somehow it does not work as expected. See https://docs.oracle.com/en/database/oracle/oracle-database/18/refrn/PDB_OS_CREDENTIAL.html and Configuring Operating System Users for a PDB

Create OS group restricted and OS user oracdb/orapdb1 with password manager to test:

groupadd restricteduseradd --create-home --gid restricted --shell /bin/bash oracdbuseradd --create-home --gid restricted --shell /bin/bash orapdb1echo manager| passwd oracdb --stdin 
echo manager| passwd orapdb1 --stdin

Setup the credentials

BEGIN    dbms_credential.create_credential(      credential_name => 'GENERIC_PDB_OS_USER',      username => 'oracdb',      password => 'manager');END;/BEGIN    dbms_credential.create_credential(      credential_name => 'PDB1_OS_USER',      username => 'orapdb1',      password => 'manager');END;/