How to start and stop Oracle database service in Linux.

You can do this task from both server and client.

1. If you do it from server then

  i. Make sure you are logged in as oracle user i.e. user which Oracle is installed and user who has all the
     rights.
 ii. Open terminal
iii. type sqlplus / as sysdba
iv. You will be logged in sql prompt. In the sql prompt just type startup. This will start your Oracle database
     service.
v.  type exit to exit from sql prompt.
vi. Now type service start lsnrctl. This will start your listener service.

You are all done.

2. If you are in  a client / remote machine then you need to have putty ssh client. Log in to oracle user
    through putty and do the same steps as mentioned above.