Issue: Expdp terminated with the below error 

ORA-39126: Worker unexpected fatal error in KUPW$WORKER.FETCH_XML_OBJECTS [INDEX:"WINDTEST5"."REPORTTEMPLATE$COMPOSITE"]

ORA-01555: snapshot too old: rollback segment number 20 with name "_SYSSMU20_980319342$" too small

ORA-06512: at "SYS.DBMS_SYS_ERROR", line 95

ORA-06512: at "SYS.KUPW$WORKER", line 11259

----- PL/SQL Call Stack -----

  object      line  object

  handle    number  name

7000100e4e7fcc0     27116  package body SYS.KUPW$WORKER

7000100e4e7fcc0     11286  package body SYS.KUPW$WORKER

7000100e4e7fcc0     13515  package body SYS.KUPW$WORKER

7000100e4e7fcc0      3173  package body SYS.KUPW$WORKER

7000100e4e7fcc0     12035  package body SYS.KUPW$WORKER

7000100e4e7fcc0      2081  package body SYS.KUPW$WORKER

70001004f4ec1c0         2  anonymous block

KUPF$FILE.WRITE_LOB

KUPF$FILE.WRITE_LOB

MD FilePieces Count: 1

FORALL

FORALL

DBMS_LOB.TRIM

DBMS_LOB.TRIM

DBMS_METADATA.FETCH_XML_CLOB

DBMS_METADATA.FETCH_XML_CLOB

In procedure DETERMINE_FATAL_ERROR with ORA-01555: snapshot too old: rollback segment number 20 with name "_SYSSMU20_980319342$" too small

Job "SYS"."SYS_EXPORT_SCHEMA_07" stopped due to fatal error at Thu Jun 23 21:29:08 2022 elapsed 0 01:49:30

Solution: For Oracle version 12c and higher:

1. restart the database

2. set the below parameter

alter system set events '10298 trace name context forever, level 32' scope=spfile;

3. Rebuild the DataPump packages with the following steps.

@$ORACLE_HOME/rdbms/admin/dpload.sql

4. Recompile invalid objects

SQL> @$ORACLE_HOME/rdbms/admin/utlrp.sql

5. If required create DATA_PUMP_DIR

5.1 Validate data pump directory 

SET LINESIZE 150

COLUMN owner FORMAT A20

COLUMN directory_name FORMAT A25

COLUMN directory_path FORMAT A80

SELECT * FROM   dba_directories ORDER BY owner, directory_name;

5.2 if required change location 

create or replace directory DATA_PUMP_DIR as '/ORAPUMPTST/PLP';

6. Start export again 

nohup expdp \'/as sysdba\' parfile=expdp_Dnt_Delet28Days_WCTST5_INC4075563.par &