How to fix for ORA-03113: end-of-file on communication channel

How to fix the issue ORA-03113: end-of-file on communication channel for Oracle Database Server 12c
When I shutdown immediate command in a running database instance. The database was busy and it took time to shut it down. So I kill the process for virtual machine server. After virtual machine restart, the database did not start any more, throwing ORA-03113 error.

[oracle@host ~]$ sqlplus / as sysdba
...
...
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Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area 2147483648 bytes
Database mounted.
ORA-03113: end-of-file on communication channel
Process ID: 4323
Session ID: 2232 Serial number: 26232

Solution

[oracle@zeus ~]$ sqlplus / as sysdba
...
...
Connected to an idle instance.

SQL> startup nomount
ORACLE instance started.

Total System Global Area 2147483648 bytes

SQL> alter database mount;

Database altered.

SQL> alter database clear unarchived logfile group 1;
Database altered.

SQL> alter database clear unarchived logfile group 2;
Database altered.

SQL> alter database clear unarchived logfile group 3;
Database altered.

SQL> shutdown immediate
ORA-01109: database not open

Database dismounted.
ORACLE instance shut down.

SQL> startup

ORACLE instance started.

Total System Global Area 2147483648 bytes

Database mounted.
Database opened.
SQL>