2745105 - Error during upgrade in phase MAIN_SHDCRE/EU_IMPORT2 - A1EEGEN 000 * db_connect failed with rc = 256

• During an update using the Software Update Manager (SUM) with the Database Migration Option an error occurs in phase MAIN_SHDCRE/EU_IMPORT2
• The following error can be found in the SAPupConsole.log

<< 2019/01/22 11:22:08 END OF PHASE MAIN_SHDCRE/EU_IMPORT2
=========== Repeat Phase ===========

Severe error(s) occurred in phase MAIN_SHDCRE/EU_IMPORT2!

Last error code set:
Found 19 aborted processes/errors in log files.
Found 9 failed import processes

*ERROR* :
The following errors were detected in the log files:

# G:\SUM\SUM\abap\load\eu_import2\EX000015_0003.LOG:
A2 EGEN 016 Bulk insert mode enabled for all tables (default).
A1 ESTA 000 Writing runtime statistics to
"G:\SUM\SUM\abap\load\eu_import2\EX000015_0003.run" every 30 sec.
A1 ETPL 002 Template 'G:\SUM\SUM\abap\load\eu_import2\DDLORA_LRG.TPL' has
version 3.
A1 EGEN 002 ====================================================
A1 EDMP 007 Memory usage: 12/0 MB buffer/disk (0 reused buffers)
A1EEGEN 000 (DBS) db_connect failed with rc = 256
A1EEGEN 000 (DBS) DbSlErrorMsg rc = 99 'all DB errors, except for ...'

Oracle Database

stopped, max proc , KBA , BC-UPG-TLS-TLA , Upgrade tools for ABAP , Problem