How can I kill all sessions connecting to my oracl

Question

I need to quickly (and forcibly) kill off all external sessions connecting to my oracle database without the supervision of and administrator.

I don't want to just lock the database and let the users quit gracefully.

How would I script this?

Answer 1

This answer is heavily influenced by a conversation here: http://www.tek-tips.com/viewthread.cfm?qid=1395151&page=3

ALTER SYSTEM ENABLE RESTRICTED SESSION;

begin     
    for x in (  
            select Sid, Serial#, machine, program  
            from v$session  
            where  
                machine <> 'MyDatabaseServerName'  
        ) loop  
        execute immediate 'Alter System Kill Session '''|| x.Sid  
                     || ',' || x.Serial# || ''' IMMEDIATE';  
    end loop;  
end;

I skip killing sessions originating on the database server to avoid killing off Oracle's connections to itself.

Answer 2

Additional info

Important Oracle 11g changes to alter session kill session

Oracle author Mladen Gogala notes that an @ sign is now required to kill a session when using the inst_id column:

alter system kill session '130,620,@1';

http://www.dba-oracle.com/tips_killing_oracle_sessions.htm

Answer 3

To answer the question asked, here is the most accurate SQL to accomplish the job, you can combine it with PL/SQL loop to actually run kill statements:

select ses.USERNAME,
    substr(MACHINE,1,10) as MACHINE, 
    substr(module,1,25) as module,
    status, 
    'alter system kill session '''||SID||','||ses.SERIAL#||''';' as kill
from v$session ses LEFT OUTER JOIN v$process p ON (ses.paddr=p.addr)
where schemaname <> 'SYS'
    and not exists
    (select 1 
        from DBA_ROLE_PRIVS 
        where GRANTED_ROLE='DBA' 
            and schemaname=grantee)
    and machine!='yourlocalhostname' 
order by LAST_CALL_ET desc;

Answer 4

Try trigger on logon

Insted of trying disconnect users you should not allow them to connect.

There is and example of such trigger.

CREATE OR REPLACE TRIGGER rds_logon_trigger
AFTER LOGON ON DATABASE
BEGIN
  IF SYS_CONTEXT('USERENV','IP_ADDRESS') not in ('192.168.2.121','192.168.2.123','192.168.2.233') THEN
    RAISE_APPLICATION_ERROR(-20003,'You are not allowed to connect to the database');
  END IF;

  IF (to_number(to_char(sysdate,'HH24'))< 6) and (to_number(to_char(sysdate,'HH24')) >18) THEN
    RAISE_APPLICATION_ERROR(-20005,'Logon only allowed during business hours');
  END IF;

END;

Answer 5

Before killing sessions, if possible do

ALTER SYSTEM ENABLE RESTRICTED SESSION;

to stop new sessions from connecting.

Answer 6

As SYS:

startup force;

Brutal, yet elegant.