Resolving ORA-39701: database must be mounted EXCLUSIVE for UPGRADE or DOWNGRADE

I was working on Database upgrade from 11.2.0.3 to 11.2.0.4 on a 2 node RAC instance.
After Installation of 11.2.0.4 software and connecting sqlplus in the new environment, Got the below error when trying to startup the database in upgrade mode


SQL> Startup upgrade
ORACLE instance started.

Total System Global Area 1.3262E+11 bytes
Fixed Size                  2304584 bytes
Variable Size            2.2481E+10 bytes
Database Buffers         1.1006E+11 bytes
Redo Buffers               74080256 bytes
Database mounted.
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-39701: database must be mounted EXCLUSIVE for UPGRADE or DOWNGRADE
Process ID: 29206
Session ID: 2002 Serial number: 3


Issue Fix
=======

I observed from the initialization parameter file, the below values are set for cluster parameters

cluster_database         = TRUE
cluster_database_instances= 2



We need to set the value of cluster_database to FALSE using the below command


SQL> alter system set cluster_database=FALSE scope=spfile sid='*' ;


Reboot the Database for the changes to be effective.
Now you will see that value of cluster_database_instances parameter is automatically changed to 1,after setting cluster_database to FALSE.


Now, the database can be started in upgrade mode without any errors.
Revert back the parameter cluster_database to TRUE, after the upgrade is completed.
The following command can be used to set cluster_database to TRUE


SQL> alter system set cluster_database=TRUE scope=spfile sid='*' ;

Restart the database.

PROCESS and DISCARD Folders IMAP

While Troubleshooting workflow relates issues in EBS, we may need to clear PROCESS and DISCARD folders under workflow user.
The below commands are useful to move folders, connecting to imap


a)Shutdown Workflow Components
b) login to imap host(e.g server1.ebs.com) as applmgr user

  $ telnet server1.ebs.com 143
  
    You will get below messages:

    ----------------------------
Trying **.**.***.**

Connected to server1.ebs.com (**.**.***.**).
Escape character is '^]'.

* OK Dovecot ready.
    ----------------------------
  i login wfmgr *****
  

  i rename PROCESS process_<sys_date>
  
 i rename DISCARD discard_<sys_date>
  

 i create PROCESS
  
i create DISCARD

i subscribe PROCESS

 i subscribe DISCARD


 i unsubscribe process_<sys_date>

 i unsubscribe discard_<sys_date>
  

c) Startup Workflow Components