Probably the undo_retention init.ora parameter is set too low relative to the time needed to complete the export, as the Oracle export engine is trying to create a read-consistent point-in-time export. The undo tablespace may need to be increased as well.

Have a look at metalink (my support) notes:

ORA-1555 When Error Exporting A Large Database [ID 174782.1]

Master Note for Export and Import [ID 1264691.1]

bg

Thank for your suggestion.

I do have a question after looked at 174782.1. if we do accordingly as it suggest, Use CONSISTENT=N during export, will it cause any data integrity issues?

It is 10gR2, not like 8i that old, right?

But it is running over a set old PA system, I think if hardware upgrade could resolve this.

Eddy

If the issue is related to data volume then, as Bill says, try increasing undo_retention or give more storage to the UNDO.

Also  are they using the query parameter to limit the amount of data exported?

If they are using 10gR2 then they should consider using datapump expdp rather than exp.

The performance difference is considerable even without using the parallel capabilities.

Not sure how you arrive at "hardware upgrade could resolve this." unless you mean making more storage available for UNDO.

There are programatic options such as saving archive data to external tables

SQL> create table system.logon_external

  2  organization external

  3  ( type oracle_datapump

  4  default directory DATA_PUMP_DIR

  5  location('SOE_LOGON_DATA01.dmp',  'SOE_LOGON_DATA02.dmp','SOE_LOGON_DATA03.dmp','SOE_LOGON_DATA04.dmp' )

  6   ) parallel 4

  7  as select /*+ PARALLEL(LOGON,4)*/ * from SYSTEM.LOSOE_LOGONIP

  8  /

Table created.

Elapsed: 00:00:05.85

SQL> !ls -altr /u01/app/oracle/admin/vm02/dpdump/*dmp

-rw-r----- 1 oracle dba 197926912 Sep 10 11:26 /u01/app/oracle/admin/vm02/dpdump/SOE_LOGON_DATA04.dmp

-rw-r----- 1 oracle dba 195923968 Sep 10 11:26 /u01/app/oracle/admin/vm02/dpdump/SOE_LOGON_DATA03.dmp

-rw-r----- 1 oracle dba 198025216 Sep 10 11:26 /u01/app/oracle/admin/vm02/dpdump/SOE_LOGON_DATA02.dmp

-rw-r----- 1 oracle dba 197861376 Sep 10 11:26 /u01/app/oracle/admin/vm02/dpdump/SOE_LOGON_DATA01.dmp

SQL>

SQL> select count(*) from system.logon_external

  2  /

  COUNT(*)

----------

  45821936

Elapsed: 00:00:00.46

SQL> truncate table SYSTEM.LOSOE_LOGONIP

  2  /

Table truncated.

Elapsed: 00:00:00.15

SQL> INSERT /*+ PARALLEL(LOSOE_LOGONIP ,4) */ INTO  SYSTEM.LOSOE_LOGONIP

select /*+ PARALLEL(LOGON,4)*/ * from SYSTEM.logon_external

  2    3

SQL> /

45821936 rows created.

Elapsed: 00:00:22.70

SQL> commit;

Commit complete.

Elapsed: 00:00:00.03

SQL> @segs SYSTEM.LOSOE_LOGONIP % %

SEGMENT NAME                                  TYPE       TABLESPACE           INITL NEXT   %INC EXT/MAX         EXT% SIZE

--------------------------------------------- ---------- -------------------- ----- ------ ---- --------------- ---- -------

1. SYSTEM.LOSOE_LOGONIP                          TABLE      SOE                    64k    1M  %    185/######      0%   912M