DBUA break then rerun doesnot recognizing the running database from older version

Error
dbua not recognizing the running database. DBUA break during upgrade.
During DBUA running, My connectivity disconnected. I have restore the database back up under the original environment (11.2.0.3) and all seems functioning.
I had to change the /ets/oratab back to the original settings.
Now, when I run dbua from the 11.2.0.4 environment it tells me the database is not running from the 11.2.0.4 home and to enter the pfile for dbua to start it.

Solution
Following things need to do before start the DBUA again.
Remove the Welcome_SID.txt file, which is located in the ORACLE_HOME/cfgtoollogs/dbua/logs/ directory.
before starting DBUA. The presence of this file indicates to DBUA that this is a re-run operation.

1. Delete the Welcome_.txt file from below directory

$ cd $ORACLE_BASE/cfgtoollogs/dbua/logs
$ rm -rf Welcome_.txt

2. Rename the DBUA folder in following location.

$ cd $ORACLE_BASE/cfgtoollogs/
$ mv dbua dbua_old

3. Before starting DBUA, leave the /etc/oratab entry as it is.
It should point to the source ORACLE_HOME only.
DBUA will take care of updating /etc/oratab file with the new ORACLE_HOME as part of upgrade.

4. Re-run the DBUA

./dbua