$ sqlplus /nolog
SQL*Plus: Release 9.2.0.8.0 - Production on Sun May 24 14:33:19 2009
Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
SQL> conn /as sysdba
Connected.
SQL> startup
ORA-01081: cannot start already-running ORACLE - shut it down first
SQL> shutdown ABORT
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 1191932384 bytes
Fixed Size 741856 bytes
Variable Size 553648128 bytes
Database Buffers 603979776 bytes
Redo Buffers 33562624 bytes
Database mounted.
Database opened.