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If required, run the following command to switch in the oracle user context:
Code Block [root@oracle12 ~]# sudo su - oracle
Run the following commands to run sqlplus and connect to DB instance:
Code Block [oracle@oracle12 ~]$ sqlplus / as sysdba
Run the following command to shut down the instance:
Code Block SQL> SHUTDOWN NORMAL
After the instance shuts down, you can quit SQL*Plus.
To know more about shutdown options see https://docs.oracle.com/cd/B19306_01/server.102/b14231/start.htm
8. Troubleshooting Oracle start
1. When starting AppBase, the software might report Oracle "ORA-12541: TNS:no listener", "ORA-12505: TNS:listener does not currently know of SID given in connect descriptor" errors.
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