The error messages were "The dbmcli call for action ACTIVATE failed. FCO-00011 The step sdb_instance_activate with step key .......... was executed with status ERROR".
When I checked the logfile XCMDOUT.LOG the last 5 lines showed:
-24988 ERR_SQL: Sql error
3, Database state: OFFLINE
6, Internal errorcode, Errorcode 9050 "disk not accessible"
My interpretation was that the database was started successfully and subsequently stopped. I verified it through manual start up of "SAPDB: NSP" in the "Services". Any help to resolve this proble will be greatly appreciated!