9. Miscellaneous Errors


ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist
Linux Error: 2: No such file or directory 

This error happens when you reboot and try to login. You will get lots of errors when the database instance is not mounted/started automatically.


  1. Check /etc/oratab and make sure that *:/opt/oracle/OraHome1 and ordb:/opt/oracle/OraHome1 are set to "Y" (YES).

  2. Try to initialize the database: $ORACLE_HOME/bin/dbstart.


No start entry for SID * at /opt/oracle/OraHome1 in /etc/oratab

This might be caused by a bug in the dbstart script which searches for the sid file in the wrong place.


  1. cp $ORACLE_BASE/admin/$ORACLE_SID/pfile/init_*.ora \


  2. As user oracle:

$ sqlplus
    SQL> create pfile from spfile;
    SQL> exit
  3. Run the dbstart script: $ORACLE_HOME/bin/dbstart.