DROP TRIGGER SYSTEM.USER_IP_LIMIT;

CREATE OR REPLACE TRIGGER SYSTEM.USER_IP_LIMIT
AFTER LOGON
ON DATABASE
DECLARE
  username   varchar2(64);
  ipinfo     varchar2(64);   
BEGIN  
    SELECT SYS_CONTEXT('USERENV', 'SESSION_USER') ,SYS_CONTEXT('USERENV', 'IP_ADDRESS')   
    INTO username,ipinfo   
    FROM dual;   
    if username='CTDSP_OEE' and ipinfo not in ('172.30.xx.xx','172.16.xx.xx','172.16.xx.xx','172.30.xx.xx','172.16.xx.xx','172.16.xx.xx','172.30.xx.xx','172.16.xx.xx','172.16.xx.xx','172.30.xx.xx','172.16.xx.xx') then
     raise_application_error(-20009,'your connection dose not permit!!!');
    end if;
END;
/
通过以上触发器的编写，来限制指定用户通过指定ip登录的限制。