Manually start the oracle____ applet under Linux under manual launch of Oracle CentOS

First, start Oracle under Linux
Log on to CentOS, switch to Oracle user rights
# su–oracle
Then enter:
$ sqlplus "/as sysdba"
The original picture will become
Sql>
Next, enter
Sql> Startup
You can start the database normally.

In addition, the instructions for stopping the database are as follows:
sql> shutdown Immediate

Second, check the Oracle DB Listener is normal
Back to Terminal mode, enter:
Sql> exit
$ LSNRCTL Status
Check to see if the listener has started

If it is not started, you can enter:
$ lsnrctl Start
Start the Listener

$ sqlplus "/as sysdba"
Sql> Conn SYS@ORCL as Sysdba
Then enter the password, sys to log into the database as SYSDBA.

Third, start Emctl
In addition, it can be found that Http://localhost.localdomain:1158/em is currently not responding, this side to start another, start the instructions are as follows:
Sql> exit
$ emctl Start Dbconsole
This instruction runs for a long time and finishes the screen as follows:

Manually Start Oracle database complete