2506981 - Error in phase RUN-OFFLINE-MIGRATION: A configuration with the path "cpacache" does already exist.

During an upgrade using Software Update manager ( SUM ) tool stops in RUN-OFFLINE-MIGRATION phase with similar error messages in following logs:

Directory:  /usr/sap/<sid>/SUM/sdt/log/SUM/RUN-OFFLINE-MIGRATION_XX.LOG

Jul 19, 2017 3:26:18 PM [Info  ]: Archive file N:\SUM\sdt\data\mig\DEPLOYARCHIVES\webdynpro~migration.sda has been extracted to directory N:/SUM/sdt/migtool/webdynpro~migration.

Jul 19, 2017 3:26:18 PM [Error ]: The following problem has occurred during step execution: com.sap.sdt.util.diag.DiagException: Could not execute migration controllers for action migrate.database;migrate.deploy;migrate.engine.data;migrate.default.data and scenario calculated executed in slot .

Error while processing migration list N:\SUM\sdt\data\mig\MIGRATIONAUSF.LST.

Could not migrate some archives from migration list.Possible reason is Database is down.Check if database running

Error during migration of archive N:\SUM\sdt\data\mig\DEPLOYARCHIVES\com.sap.aii.af.cpa.svc.migration.sda which has been extracted to directory N:/SUM/sdt/migtool/com.sap.aii.af.cpa.svc.migration.Possible reason is Database is down.Check if database running

Could not execute MTI process. See log files N:\SUM\sdt\log\SUM\JMT_FRAMEWORK_12.OUT and N:\SUM\sdt\log\SUM\JMT_FRAMEWORK_12.ERR.

Return code condition success evaluated to false for process java.exe for action RUN_MTI.

Error: URI=null Line=2: cvc-elt.1: Cannot find the declaration of element 'migration'.

Warning: validation was turned on but an org.xml.sax.ErrorHandler was not set, which is probably not what is desired.  Parser will use a default ErrorHandler to print the first 0  errors.  Please call the setErrorHandler method to fix this.

Error: URI=null Line=2: cvc-elt.1: Cannot find the declaration of element 'migration'.

Directory:  /usr/sap/<sid>/SUM/sdt/log/SUM/MTI_COM_SAP_AII_AF_CPA_SVC_MIGRATION_ENGINE_DATA_MC_07

<!--NAME[N:\SUM\sdt\log\SUM\MTI_COM_SAP_AII_AF_CPA_SVC_MIGRATION_ENGINE_DATA_MC_07.ERR]/-->

Jul 19, 2017 3:25:31 PM  com.sap.aii.af.service.cpa.migration.com_sap_aii_af_cpa_svc_migration.engine_data_mcerr [Thread[main,5,main]] Error: Error while migrating controller com.sap.aii.af.service.cpa.migration.CPACacheDataMigrationController. CSN component - BC-XI-CON-AFW . Reason: "A configuration with the path "cpacache" does already exist."

Jul 19, 2017 3:25:31 PM  com.sap.aii.af.service.cpa.migration.com_sap_aii_af_cpa_svc_migration.engine_data_mcerr [Thread[main,5,main]] Error:

Upgrade of JAVA/Dual stack system using SUM tool

cpacache, MIGRATIONAUSF, RUN-OFFLINE-MIGRATION , KBA , BC-UPG-TLS-TLJ , Upgrade tools for Java , Problem