Enterprise Server has a set of default users that are used when no user is logged on for 
               		
CICS, JES, IMS or, 
                  		ESMAC authentication
. These users and the associated environment variables are: 
               	 
               
                   
                     		   
                     		   
                     		   
                     		  
                      
                        			 
                         
                           				
                           | Environment | User | Associated Environment Variable | 
 
                        		  
                      
                     		  
                      
                        			 
                         
                           				
                           | ESMAC | mfuser | ES_USR_DFLT_ESMAC | 
 
                        			 
                         
                           				
                           | CICS | CICSUSER | ES_USR_DFLT_CICS | 
 
                        			 
                         
                           				
                           | JES | JESUSER | ES_USR_DFLT_JES | 
 
                        			 
                         
                           				
                           | IMS | IMSUSER | ES_USR_DFLT_IMS | 
 
                        		  
                      
                     		
                  
                 
               	 
            Using the environment variables, the default users can be overwritten by the users of your choice. For instance we could overwrite
               the ESMAC default user using in the region configuration. 
               	 
            
 
            	 configuration:
[ES-Environment]
ES_USR_DFLT_ESMAC=ESMACUSR
 
            	 Note: JCL job submission through 
               		ESCWA and the IDE will fallback to the ESMAC default user unless the 
               		ESCWA JES Default User Job Submission property has been set in the Advanced Region Properties page in 
               		ESCWA, in this case it will fallback to the JES default user.