start

$ su - oracle
$ lsnrctl start

sqlplus /nolog

SQL> conn /as sysdba
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area bytes
Fixed Size           bytes
Variable Size          bytes
Database Buffers       bytes
Redo Buffers            bytes
Database mounted.
Database opened.SQL>

su - oracle
$ sqlplus /nolog
SQL>conn /as sysdba
Connected.
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

SQL> exit  

$ lsnrctl stop

export ORACLE_HOME=`` ORACLE_SID=``