How to resolve errors when starting Oracle database on Linux?

To solve the issue of Oracle database error during Linux startup, you can try the following methods:

1. Check the log files of the Oracle database to find specific error messages. Typically, the log files of the Oracle database are located in the $ORACLE_BASE/diag/rdbms///trace directory. You can view the alert_.log file to get detailed error information.
2. Make sure that the relevant environment variables for the Oracle database are set correctly, including ORACLE_HOME and ORACLE_SID. You can check the values of these environment variables by using echo $ORACLE_HOME and echo $ORACLE_SID.
3. To check the status of an Oracle database instance, you can connect to the database instance using SQL*Plus or lsnrctl command, and then execute select status from v$instance; to see if the database instance is functioning normally.
4. You can check if the Oracle database listener is running properly by using the command lsnrctl status to view the status of the listener.
5. Check if the resources of the Linux system are sufficient, including memory, disk space, and other resources.

If the above methods do not resolve the issue, it is recommended to try restarting the Oracle database or the Linux system. Sometimes this can solve some startup problems. If the issue persists, it is advisable to consult the official Oracle documentation or seek help from Oracle technical support.