PostgreSQL 8.x.y
WAL: Write-Ahead Logging

To archive WAL at /var/lib/pgsql/data/pg_xlog/,
Please add archive-command at /var/lib/pgsql/data/postgresql.conf

#archive_command = ''   # command to use to archive a logfile
                        # segment
archive_command = 'cp %p /home/postgres/pgbackup/%f'

/var/lib/pgsql/data/pg_xlog/ will be erased after archived.
