Cannot Backup

Question

I get the following message when i try to backup Oracle Xe 10g Express Edition:
Backup of the Database failed
unknown log mode: SP2-0640
Log file is: SP2-0640
Error
Please help

Answer 1

Online backups require archivelog mode, if you're trying to `alter database begin backup;` here's the xe doc for how-to change the log mode http://download.oracle.com/docs/cd/B25329_01/doc/admin.102/b25107/backrest.htm#CIHDGJAB
If you just want to have a copy of the datafiles, get a controlfile trace, note the names/locations of all the datafiles, shut it down and copy away.
> $ sqlplus /nolog
> SQL> conn /as sysdba;
> SQL> alter database backup controlfile to trace;
> SQL> show parameter user_dump
> ... user_dump_dest folder will have a trace file with SQLs to recreate the controlfile
> SQL> select name from v$datafile;
> ... here's the files to copy
> SQL> shutdown immediate;
> SQL> exit;
> $ ... copy the datafiles someplace safe
> $ sqlplus /nolog
> SQL> conn /as sysdba;
> SQL> startup;