oracle11g password setting

Viewing Password Settings:

These new settings can be seen by running the below query.

SELECT profile, resource_name, limit
FROM dba_profiles
WHERE profile='DEFAULT';

Resource Name
Oracle Database 11g

Failed_login_attempts 10
Password_grace_time 7 (days)
Password_life_time 180
Password_lock_time 1 (days)
Password_reuse_max Unlimited
Password_reuse_time Unlimited

To size undo tablespace properly

To properly size the UNDO tablespace, it is suggested that you actually observe the workload through the system. After a good workload has been given to the system, you can use the following code to ask Oracle to determine the proper sizing for an UNDO tablespace.
SQL> SET SERVEROUTPUT on
SQL> DECLARE
utbsiz_in_MB NUMBER;
BEGIN
utbsiz_in_MB := DBMS_UNDO_ADV.RBU_MIGRATION;
dbms_output.put_line('undo size : '||utbsiz_in_MB||'MB');
end;
/
undo size : 2800MB
PL/SQL procedure successfully completed.
Run this package during peak hours ie when the load is more in this case it is suggested that we need to set undo tbs to 2800M

RMAN-03009: ORA-00230: operation disallowed: snapshot control file enqueue unavailable

RMAN-03009: failure of Control File and SPFILE Autobackup command on dev_0 channel at 03/23/2007 01:35:21
ORA-00230: operation disallowed: snapshot control file enqueue unavailable


RMAN-03009: failure of Control File and SPFILE Autobackup command on dev_0 channel at 03/23/2007 01:35:21
ORA-00230: operation disallowed: snapshot control file enqueue unavailable
This is due to some job is doing the same activity ie duplicate job running against the db

There may be another job is holding the controlfile ie there may be chances of backup running by another job on same DB just check
Is there another rman backup running and backing up the control file at the same time?

specification does not match any archive log in the recovery catalog

In rman log message

RMAN> connect target *
2> crosscheck archivelog all;
3> list archivelog until time 'sysdate-3';
4> delete noprompt archivelog until time 'sysdate-3';
5>
specification does not match any archive log in the recovery catalog

This can be ignored

It is simply saying that there are no archive logs earlier than 3 days found for deletion

Cross check : on archive dest you will not have archivelogs older than 3 days