Situation

After setting up XA Open String values in the MF secrets vault then on region start XA Open was returning -3.
  

Resolution

The XA open string was defined incorrectly as:
 

DSN=DBD1,USRPASS=&USER&.&PWD&

and it should be defined as FALSEUSER:
 

DSN=DBD1,USRPASS=&FALSEUSER&.&PWD&

Once XA open string was set correctly xa open established a connection to the DB2 database.

 

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