Oracle Database Discussions

Hi,

Sometimes some DBs on a host is facing an issue weherein when connected from appication host is showing the below error....

sqlplus apps/pass

TNS connection closed

and when logged into the DB is showing ....

select name from v$database;
select name from v$database
*
ERROR at line 1:
ORA-01012: not logged on
Process ID: 0
Session ID: 0 Serial number: 0

.....

the solution is to shut immediate/abort the instance...

Anyone please let me know why this is happening now and again...and how to resolve this issue permanently

Thanks
Joseph