COLD BACKUP & RECOVERY SCENARIOS.pdf

8/10/2019 COLD BACKUP & RECOVERY SCENARIOS.pdf

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BACKUP AND RECOVERY USING COLD BACKUP | ARCHIVELOG Vs NOARCHIVELOG

Exploring the Oracle DBA Technology by Gunasekaran , Thiyagu

DATABASE RECOVERY

Database Recovery having 2 types.

COMPLETE - NO DATA LOSS

INCOMPLETE- DATA LOSS (CAN RECOVER TO A CERTAIN TIME OR SCN).

We can perform complete recovery, if we lost only datafiles.

We can perform incomplete recovery, if we lost either redolog files, control files, archivelog

files.

INCOMPLETE RECOVERY is possible in 3 ways.

UNTIL SCN

UNTIL TIME

UNTIL CANCEL (Always we can use this method).

RECOVER CRD FILES IN NOARCHIVELOG MODE

SYS>select name, log_mode, open_mode from v$database;

NAME LOG_MODE OPEN_MODE

--------- ------------ ----------

ROSE NOARCHIVELOGREAD WRITE

SYS> shut immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

$cd /u01/app/oracle/oradata/rose/

$cp *.* /u03/coldbkp/

SQL> startup

ORACLE instance started.

..

....

[Trimmed]

Database opened.

SYS> conn sham/sham

Connected.

SHAM>create table tab2 as select * from tab1;

Table created.

SHAM>select count(*) from tab2;

COUNT(*)----------524288


$rm *.*


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SYS>shut abort;


$cd /u03/coldbkp/

[oracle@oel5 coldbkp]$ cp */u01/app/oracle/oradata/rose/

SYS>startup


..

....

[Trimmed]

Database opened.

SYS>conn sham/sham

Connected.


select count(*) from tab2

*

ERROR at line 1:

ORA-00942: table or view does not exist

RECOVER CRD FILES IN ARCHIVELOG MODE

SYS>select status from v$instance;

STATUS

------------

OPEN

SYS>alter database close;

Database altered.

SYS>alter database archivelog;

Database altered.

SYS>startup


..

....

[Trimmed]

Database opened.

SYS> select name, log_mode, open_mode from v$database;


--------- ------------ ----------

ROSE ARCHIVELOG READ WRITE

SYS>shut immediate;

Database closed.




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SYS>startup


..

....

[Trimmed]

Database opened.

SYS>archive log list;

Database log mode Archive Mode

Automatic archival Enabled

Archive destination USE_DB_RECOVERY_FILE_DEST

Oldest online log sequence 88Next log sequence to archive 90

Current log sequence 90

SYS>conn sham/sham

Connected.


Table created.

SHAM>insert into tab2 select * from tab1;

524288 rows created.

SHAM> /


SHAM> /


SHAM> /


SHAM>commit;

Commit complete.


COUNT(*)

----------

4718592





Oldest online log sequence 104

Next log sequence to archive 106



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[oracle@oel5 rose]$rm -rf *

[oracle@oel5 rose]$ls -l

total 0


ORA-00210: cannot open the specified control file

ORA-00202: control file: '/u01/app/oracle/oradata/rose/control01.ctl'

ORA-27041: unable to open file

Linux Error: 2: No such file or directory

Additional information: 3

SYS>shut abort;


$cd /u03/coldbkp/[oracle@oel5 coldbkp]$cp* /u01/app/oracle/oradata/rose/

SYS>startup mount;


..

[Trimmed]

Database mounted.

SYS>select file#, checkpoint_change# from v$datafile;

FILE# CHECKPOINT_CHANGE#

--------- ------------------

1 714338

2 714338

3 714338

4 714338

5 714338

SYS>alter database recover automatic using backup controlfile until cancel;

alter database recover automatic using backup controlfile until cancel

*

ERROR at line 1:

ORA-00279: change 736465 generated at 09/22/2014 19:48:08 needed for thread 1

ORA-00289: suggestion:

/u01/app/oracle/flash_recovery_area/ROSE/archivelog/2014_09_22/o1_mf_1_106_%u_.arc

ORA-00280: change 736465 for thread 1 is in sequence #106

ORA-00278: log file

'/u01/app/oracle/flash_recovery_area/ROSE/archivelog/2014_09_22/o1_mf_1_106_%u_.arc'

no longer needed for this recovery

ORA-00308: cannot open archived log

'/u01/app/oracle/flash_recovery_area/ROSE/archivelog/2014_09_22/o1_mf_1_106_%u_.arc'

ORA-27037: unable to obtain file status




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SYS>recover cancel;

Media recovery complete.

SYS>@df.sql;

FILE# CHECKPOINT_CHANGE#

---------- -----------------

1 736465

2 736465

3 736465

4 736465

5 736465

SYS>select open_resetlogs from v$database;

OPEN_RESETL

-----------REQUIRED

SYS>alter database open resetlogs;

Database altered.








SHAM>conn sham/sham

Connected.


COUNT(*)

----------

3670016

NOTE: We performed recovery, but it is Incomplete Recovery.

LOSS OF NON SYSTEM DATAFILE

SYS>select name, log_mode, open_mode from v$database;


--------- ------------ ----------

ROSE ARCHIVELOGREAD WRITE

SYS>conn sham/sham

Connected.


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COUNT(*)

----------

150000


COUNT(*)

----------

150000

SYS>archive log list







SYS>shut immediate;

Database closed.





SYS> startupORACLE instance started.

..

[Trimmed]

Database opened.

SHAM> insert into tab1 select * from tab1;


SHAM>/


SHAM>/600000 rows created.

SHAM>insert into tab2 select * from tab1;


SHAM>/


SHAM>/



COUNT(*)

----------

1200000


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COUNT(*)

----------

2400000

SHAM>commit;

Commit complete.








SYS>select name from v$datafile;

NAME

--------------------------------------------

/u01/app/oracle/oradata/rose/system01.dbf

/u01/app/oracle/oradata/rose/undotbs01.dbf

/u01/app/oracle/oradata/rose/sysaux01.dbf

/u01/app/oracle/oradata/rose/users01.dbf

/u01/app/oracle/oradata/rose/example01.dbf

SYS> !rm -rf /u01/app/oracle/oradata/rose/users01.dbf

SYS>create table tab3 as select * from tab2;

create table tab3 as select * from tab2

*

ERROR at line 1:

ORA-01116: error in opening database file 4

ORA-01110: data file 4: '/u01/app/oracle/oradata/rose/users01.dbf'




SYS>alter database datafile 4 offline;

Database altered.

SYS> select file#, status from v$datafile where file#=4;

FILE# STATUS

-------- -----

4 RECOVER

SYS>select * from v$recover_file;

FILE# ONLINE_STATUS ERROR

------ ------------ -------------

4 OFFLINE FILE NOT FOUND


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SHAM>select * from tab;

TNAME TABTYPE CLUSTERID

------------------------------ ------- ----------

TAB1 TABLE

TAB2 TABLE

SYS>shut immediate;

Database closed.





SYS>startup


..

...

[Trimmed]

Database opened.

SYS>conn sham/sham

Connected.


Table created.


Table created.

SHAM>update tab4 set name='ROSELIN';

1200000 rows updated.

SHAM>update tab3 set name='ROSELIN';










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$pwd

/u01/app/oracle/oradata/rose

$rm *.ctl

$ls *.ctl

ls: *.ctl: No such file or directory

SQL>select name from v$datafile;

select name from v$datafile

*

ERROR at line 1:






SQL>shut abort;


$ cd /u02/coldbkp/

$cp *.ctl /u01/app/oracle/oradata/rose/

SYS>startup mount;


..

....

[Trimmed]

Database mounted.

SYS>recover database using backup controlfile until cancel;

auto

...

ORA-01547: warning: RECOVER succeeded but OPEN RESETLOGS would get error below

ORA-01194: file 1 needs more recovery to be consistent

ORA-01110: data file 1: '/u01/app/oracle/oradata/rose/system01.dbf'

SYS>recover cancel;

SYS>select member from v$logfile;

MEMBER

-----------------------------------------

/u01/app/oracle/oradata/rose/redo03.log



SYS>recover database using backup controlfile until cancel;

ORA-00279: change 1544063 generated at 09/24/2014 15:23:22 needed for thread 1ORA-00289: suggestion:

/u01/app/oracle/flash_recovery_area/ROSE/archivelog/2014_09_24/o1_mf_1_25_%u_.arc


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Specify log: {=suggested | filename | AUTO | CANCEL}


Log applied.


SYS> recover cancel;


Database altered.



------------------------------ ------- ----------

TAB4 TABLE

TAB1 TABLE

TAB2 TABLE

TAB3 TABLE

LOSS OF REDOLOG FILES IN ARCHIVELOG MODE

SYS>select name, log_mode from v$database;

NAME LOG_MODE--------- ------------ROSE ARCHIVELOG

SYS>archive log list;Database log mode Archive Mode






SYS>select member from v$logfile;

MEMBER

-----------------------------------------/u01/app/oracle/oradata/rose/redo03.log



SYS>select group#, thread#, sequence#, members, archived, status from v$log;

GROUP# THREAD# SEQUENCE# MEMBERS ARC STATUS

---------- ------- ---------- ---------- --- --------

1 1 1 1 NO CURRENT

2 1 0 1 YES UNUSED

3 1 0 1 YES UNUSED

SYS>conn sham/sham

Connected.


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------------------------------ ------- ----------

TAB1 TABLE

SYS>shut immediate;

Database closed.





SYS>startup


..

....

[Trimmed]

Database opened.

SYS>conn sham/sham

Connected.


Table created.

SHAM>create table tab3 as select * from tab1;Table created.


Table created.

SHAM>update tab1 set name='JO' where id >= 1 and id update tab2 set name='JOE' where id >=1 and id update tab3 set name='JYO_JO' where id >= 1 and id commit;

Commit complete.

SHAM>select name from tab4 where id=1 or id=2;

NAME

Jo

Jo

SHAM>update tab4 set name='rosalin' where id>=1 and id


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STEPS TO RECOVER REDO LOG FILES IN NOARCHIVE MODE

STEP 1: SQL> shut immediate;

STEP 2: SQL>! cp /u03/coldbkp/*.dbf /u01/app/oracle/product/oradata/sham/

STEP 3: SQL>! cp /u03/coldbkp/*.ctl /u01/app/oracle/product/oradata/sham/Step 4: SQL> recover database until cancel;

STEP 5: SQL> alter database open resetlogs;

LOSS OF REDO LOG FILES IN NOARCHIVE MODE


NAME LOG_MODE

--------- ------------

ROSE NOARCHIVELOG

SYS>conn sham/sham

Connected.



------------------------------ ------- ----------

TAB1 TABLE

SYS>shut immediate;

Database closed.





SYS> startup


..

....

[Trimmed]

Database opened.

SYS>conn sham/sham

Connected.


Table created.


Table created.


Table created.


[oracle@oel5 rose]$rm -rf *.log


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SYS>shut abort;


$cd /u02/coldbkp/

[oracle@oel5 coldbkp]$cp *.dbf /u01/app/oracle/oradata/rose/

[oracle@oel5 coldbkp]$cp *.ctl /u01/app/oracle/oradata/rose/

SYS>startup mount;


..

....

[Trimmed]

Database mounted.

SYS>recover database until cancel;


SYS>conn sham/sham

Connected.

SHAM>select * from tab2;

select * from tab2

*

ERROR at line 1:

ORA-00942: table or view does not exist

LOSS OF SYSTEM TABLESPACE

SQL>select name, log_mode from v$database;

NAME LOG_MODE

--------- ------------

ROSE ARCHIVELOG

SQL>select name from v$datafile;

NAME

--------------------------------------------






SYS>shut immediate;

Database closed.






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SYS>startup


..

....

[Trimmed]

Database opened.

LOS S OF DATA FILE WHICH WAS NOT IN THE BACKUP

SQL>select name, log_mode from v$database;

NAME LOG_MODE

--------- ------------

ROSE ARCHIVELOG

SYS>shut immediate;

Database closed.




$cp *.* /u03/coldbkp/rose

SYS>startup


Total System Global Area 746586112 bytes

Fixed Size 1275920 bytes

Variable Size 197134320 bytes

Database Buffers 545259520 bytes

Redo Buffers 2916352 bytes

Database mounted.

Database opened.








SYS>select name from v$datafile;

NAME

------------------------------------------







17/33



SYS>create tablespace sample datafile '/u01/app/oracle/oradata/rose/test01.dbf' size 10m;

Tablespace created.

SYS>grant connect, resource to rose identified by rose;

Grant succeeded.

SYS>alter user rose default tablespace sample;

User altered.

SYS>select username, default_tablespace from dba_users where username='ROSE'

USERNAME DEFAULT_TABLESPACE

------------------------------ ----------------------

ROSE SAMPLE

SYS>conn rose/rose

Connected.

ROSE>create table tab1(id number ,

name varchar2(15),

qual varchar2(15),

city varchar2(15),

mobile number);

Table created.

ROSE>begin

for i in 1..400000 loop

insert into tab1 values(i,'rosalin','m.sc','chennai',1234554321);

commit;

end loop;

end;

/

PL/SQL procedure successfully completed.

ROSE>select count(*) from tab1;

COUNT(*)

-------

4000000

SYS> !rm /u01/app/oracle/oradata/rose/sample01.dbf

SYS> !ls /u01/app/oracle/oradata/rose/sample01.dbf

ls: /u01/app/oracle/oradata/rose/sample01.dbf: No such file or directory

SYS>conn rose/rose

Connected.

ROSE>update tab1 set name='JO' where id>=1 and id


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ROSE>update tab1 set name='JYO' where id >= 5001 and id update tab1 set name='JYOTIKA' where id >= 10001 and id commit;

Commit complete.

ROSE>create table tab2 as select * from tab1;

create table tab2 as select *from tab1

*

ERROR at line 1:


ORA-01110: data file 6: '/u01/app/oracle/oradata/rose/sample01.dbf'




SYS>alter tablespace sample offline immediate; or

Tablespace altered.

SYS>alter database datafile 6 offline;

Database altered

SYS>alter database create datafile '/u01/app/oracle/oradata/rose/sample01.dbf'; (or)

SYS>alter database create datafile '/u01/app/oracle/oradata/rose/sample01.dbf' as/u01/app/oracle/oradata/rose/sample01.dbf';

Database altered.

SYS>alter tablespace sample online;

alter tablespace sample online

*

ERROR at line 1:

ORA-01113: file 6 needs media recovery if it was restored from backup, or END

BACKUP if it was not

ORA-01110: data file 6: '/u01/app/oracle/oradata/rose/sample01.dbf'

SYS>recover tablespace sample;


ORA-00289: suggestion :

/u01/app/oracle/flash_recovery_area/ROSE/archivelog/2014_10_01/o1_mf_1_4_b2p6cf6q_.arc



auto

..

...

[Trimmed]

Log applied.



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SYS>altter tablespace sample online;

Tablespace altered.

SYS>select * from tab1 where id=1001 or id=1002;

ID NAME QUAL CITY MOBILE

------ ------- ------- --------- ----------

1001 JO m.sc chennai 1234554321

1002 JO m.sc chennai 1234554321

LOSS OF SINGLE CONTROL FILE


NAME LOG_MODE

--------- ------------ROSE ARCHIVELOG

SYS> select name from v$controlfile;

NAME

--------------------------------------------

/u01/app/oracle/oradata/rose/control01.ctl




$rm control03.ctl

SYS>update rose.tab1 set name='ORACLE';


SYS>select current_scn from v$database;

select current_scn from v$database

*

ERROR at line 1:



ORA-27041: unable to open file Linux Error: 2: No such file or directory

SYS> shut abort;



$cp control01.ctl /u03/app/oracle/oradata/rose/control03.ctl

SYS>startup


..

....[Trimmed]

Database opened.


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SYS> select * from rose.tab1 where id=1 or id=2;


--- ------- ---------- ---------- -------------

1 ORACLE m.sc chennai 1234554321

2 ORACLE m.sc chennai 1234554321

LOSS OF UNDO TABLESPACE

SYS> select name, log_mode from v$database;

NAME LOG_MODE

--------- ------------

ROSE ARCHIVELOG

SYS> select name from v$datafile;

NAME

-------------------------------------------


/u01/app/oracle/oradata/rose/untbs01.dbf




SYS> show parameter undo;

NAME TYPE VALUE

------------------------------------ ----------- ----------

undo_management string AUTO

undo_retention integer 900

undo_tablespace string UNDOTBS1

SYS>shut immediate;

Database closed.





SYS>startup


..

....

[Trimmed]

Database opened.

SYS> conn rose/rose

Connected.

ROSE> update tab1 set name='JO_JYO';



21/33



$rm /u01/app/oracle/oradata/rose/undotbs01.dbf

$ls /u01/app/oracle/oradata/rose/undotbs01.dbf

ls: /u01/app/oracle/oradata/rose/undotbs01.dbf: No such file or directory

ROSE> update rose.tab1 set name='JO';

update tab1 set name='JO'*

ERROR at line 1:


ORA-01110: data file 2: '/u01/app/oracle/oradata/rose/undotbs01.dbf'




SYS> alter database datafile 2 offline;

alter database datafile 2 offline

*

ERROR at line 1:

ORA-00603: ORACLE server session terminated by fatal error

SYS> select file#, name , status from v$datafile;

FILE# NAME STATUS

1 /u01/app/oracle/oradata/rose/system01.dbf SYSTEM

2 /u01/app/oracle/oradata/rose/undotbs01.dbf RECOVER

3 /u01/app/oracle/oradata/rose/sysaux01.dbf ONLINE

4 /u01/app/oracle/oradata/rose/users01.dbf ONLINE

5 /u01/app/oracle/oradata/rose/example01.dbf ONLINE

$cd /u03/coldbkp/rose/

$cp undotbs01.dbf /u01/app/oracle/oradata/rose/

ROSE> update rose.tab3 set name='JYO_JO';

update rose.tab3 set name='JYO_JO'

*

ERROR at line 1:

ORA-01122: database file 2 failed verification check

ORA-01110: data file 2: '/u01/app/oracle/oradata/rose/undotbs01.dbf'

ORA-01208: data file is an old version - not accessing current version

SYS> recover datafile 2;


ORA-00289: suggestion:

/u01/app/oracle/flash_recovery_area/SHAM/archivelog/2014_10_10/o1_mf_1_2_b3j64mkm_.arc



auto

..

[Trimmed]

Log applied.



22/33


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$mv undotbs01.dbf undotbs01.dbfx

[oracle@oel5 sham]$ ls -l undo*

-rw-r----- 1 oracle oinstall 293609472 Oct 12 19:59 undotbs01.dbfx

SYS> startup;


.

..

[Trimmed]

Database mounted.

ORA-01157: cannot identify/lock data file 2 - see DBWR trace file

ORA-01110: data file 2: '/u01/app/oracle/oradata/sham/undotbs01.dbf'

SYS> alter system set undo_management='manual' scope=spfile;

System altered.


ORA-01109: database not open



SYS> startup


.

..

[Trimmed]

Database mounted.

ORA-01157: cannot identify/lock data file 2 - see DBWR trace file

ORA-01110: data file 2: '/u01/app/oracle/oradata/sham/undotbs01.dbf'


NAME TYPE VALUE

------------------------------------ ----------- --------

undo_management string MANUAL


undo_tablespace string UNDOTBS1

SYS>alter database datafile'/u01/app/oracle/oradata/rose/undotbs01.dbf' offline drop; (or)

SYS> alter database datafile 2 offline drop;

Database altered.

SYS> alter database open;

Database altered.

SYS> drop tablespace undotbs1;

Tablespace dropped.

SYS>create undo tablespace undotbs datafile '/u01/app/oracle/oradata/sham/untbs01.dbf' size 50m;

Tablespace created.


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SYS> alter system set undo_tablespace='undotbs' scope=spfile;

System altered.

SYS> alter system set undo_management='auto' scope=spfile;

System altered.

SYS>shut immediate;

Database closed.



SYS> startup;


Total System Global Area 746586112 bytes..

[Trimmed]

Database mounted.Database opened.


NAME TYPE VALUE

------------------------------------ ----------- ------------------------------

undo_management string AUTO


undo_tablespace string undotbs


NAME

--------------------------------------------

/u01/app/oracle/oradata/sham/system01.dbf

/u01/app/oracle/oradata/sham/untbs01.dbf

/u01/app/oracle/oradata/sham/sysaux01.dbf

/u01/app/oracle/oradata/sham/users01.dbf

/u01/app/oracle/oradata/sham/example01.dbf

LOSS OF SYSAUX TABLESPACE


NAME LOG_MODE

--------- ------------

ROSE ARCHIVELOG

SYS> archive log list;







25/33




NAME

--------------------------------------------






SYS>shut immediate;

Database closed.





SYS>startup


..

....

[Trimmed]

Database opened.

SHAM> update tab1 set name='JO';


SHAM> update tab2 set name='JYO';


$mv sysaux01.dbf sysaux01.dbfx

$ls -l sysaux01.dbfx

-rw-r----- 1 oracle oinstall 251666432 Oct 12 22:27 sysaux01.dbfx

SYS> alter tablespace sysaux offline;

alter tablespace sysaux offline

*

ERROR at line 1:ORA-01116: error in opening database file 3

ORA-01110: data file 3: '/u01/app/oracle/oradata/rose/sysaux01.dbf'





[oracle@oel5 sham]$cp sysaux01.dbf /u01/app/oracle/oradata/rose/

SYS> recover datafile 3;

ORA-00283: recovery session canceled due to errors

ORA-01124: cannot recover data file 3 - file is in use or recovery

ORA-01110: data file 3: '/u01/app/oracle/oradata/rose/sysaux01.dbf'


26/33


27/33



SYS> grant connect, resource to sham identified by sham;

Grant succeeded.

SYS> conn sham/sham

Connected.

SHAM> set time on;

17:29:44SHAM> @sample.sql;

Table created.

PL/SQL procedure successfully completed.

17:32:12SHAM> select * from tab1 where id=1;


-- -------- -------- ------- ----------

1 rosalin m.sc chennai 1234554321

17:32:57 SHAM> update tab1 set name='oracle';


17:33:27 SHAM> commit;

Commit complete.

17:33:32 SHAM>update tab1 set name='ORACLEDB' where id=1000;

1 row updated.

17:34:23 SHAM> conn / as sysdbaConnected.

17:35:06 SYS>alter system switch logfile;

System altered.

17:35:12 SYS> /

System altered.

17:35:12 SYS> /

System altered.

17:35:18 SYS> drop user sham cascade;

User dropped.

17:35:57 SYS> shut immediate;

Database closed.



$mv *.dbf /u01/

$ls -l *.dbf

ls: *.dbf: No such file or directory


[oracle@oel5 rose]$cp *.dbf /u01/app/oracle/oradata/rose/


28/33



17:36:24 SYS>startup mount


..

....

[Trimmed]Database mounted.

17:44:32 SYS>recover automatic database until time '2014-10-15 17:35:10';


17:52:50 SYS> alter database open resetlogs;

Database altered.

17:53:35 SYS> conn sham/sham

Connected.

SHAM> select * from tab;


------------------------------ ------- ----------

TAB1 TABLE

SHAM> select * from tab1 where id=1 or id=1000;


---- ------ --------------- ------- -----------

1 oracle m.sc chennai 1234554321

1000 ORACLEDB m.sc chennai 1234554321

POINTS TO NOTE

To recover to a past point in time you have to RESTORE the database from a backup older than the

recovery point in time. Make a new complete backup, as the database is open in a new incarnation

and previous archived log are not relevant.

LOSS OF TEMPORARY TABLESPACE


NAME LOG_MODE

--------- ------------

ROSE ARCHIVELOG

SYS> select * from v$tablespace;

TS# NAME INC BIG FLA ENC

---------- ------------------------------ --- --- --- ---

0 SYSTEM YES NO YES

1 UNDOTBS1 YES NO YES

2 SYSAUX YES NO YES

4 USERS YES NO YES

3 TEMP NO NO YES

6 EXAMPLE YES NO YES

6 rows selected.


29/33



SYS> select name from v$tempfile;

NAME

----------------------------------------

/u01/app/oracle/oradata/rose/temp01.dbf


Database closed.





$rm /u01/app/oracle/oradata/rose/temp01.dbf

SYS>startupORACLE instance started.

..

....

[Trimmed]

Database opened.

$ tail -f /u01/app/oracle/admin/rose/bdump/alert_rose.log

...

Re-creating tempfile /u01/app/oracle/oradata/rose/temp01.dbf

From 10g, Oracle is able to detect the missing temporary file and recreate it on the same location.

SCENARIO II

SYS> select file#, name, status from v$tempfile;

FILE# NAME

------ -----------------------------------------

1 /u01/app/oracle/oradata/rose/temp01.dbf

$ rm /u01/app/oracle/oradata/rose/temp01.dbf

SYS> conn sham/sham

Connected.

SHAM> select * from tab1 order by id DESC;

..

...

more rows are displayed

$ tail -f /u01/app/oracle/admin/rose/bdump/alert_rose.log


ORA-01110: data file 201: '/u01/app/oracle/oradata/rose/temp01.dbf'




30/33



SYS> create temporary tablespace temptbs tempfile

'/u01/app/oracle/oradata/rose/temp01.dbf' size 10m;

Tablespace created.

SYS> alter database default temporary tablespace temptbs;

Database altered.

SYS> drop tablespace temp;

Tablespace dropped.

SYS> select * from v$tablespace;

TS# NAME INC BIG FLA ENC

---------- ----- ---- ----- -----

0 SYSTEM YES NO YES

1 UNDOTBS1 YES NO YES2 SYSAUX YES NO YES

4 USERS YES NO YES

6 EXAMPLE YES NO YES

7 TEMPTBS NO NO YES

6 rows selected.

SYS> select name from v$tempfile;

NAME

-----------------------------------------

/u01/app/oracle/oradata/rose/temp01.dbf

POINTS TO NOTE

UNIX/LINUX provide us with a command that does a safer remove.

$rm -i

$rm -i undotbs01.dbfx

rm: remove regular file `undotbs01.dbfx'?

RECOVERY COMMANDS POINTS TO NOTE

SQL> alter database recover automatic using backup controlfile until cancel;

SQL> recover database using backup controlfile until cancel;

SQL> recover database until cancel;

ALTER DATABASE is the basic SQL command to recover. RECOVER is an SQL command that automates

that, asking for the next archivelog. It is the recommended way (from sqlplus or rman).

USING BACKUP CONTROLFILE tells Oracle to assume that there are transactions and redo beyond the

controlfile that is used. i.e. It tells to oracle that you don't have the current control file.

So the recovery should continue beyond what is recorded in the control file. And you will need

to open resetlogs at the end to restart a redo log sequence.


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STEPS TO RECOVER NON SYSTEM TABLESPACE IS MISSING

Recovery of a missing datafile that has no backups (DB is up and running )

Pre Requisites: All relevant archived logs.

STEP 1 alter tablespace offline immediate;

STEP 2 alter database create datafile '/path/filename.dbf';

STEP 3 recover tablespace ;

STEP 4 alter tablespace online;

If the create datafile command needs to be executed to place the datafile on a location different

than the original always use following query given below.

SQL>alter database create datafile '/u01/data/newdata01.dbf' as '/u02/data/newdata01.dbf

If aNON SYSTEMdatafile that was not backed up since the last backup is missing, recovery can

be performed if allarchived logs since the creation of the missing datafile exist.

Complete Open Database Recovery (Database is Initially closed)

If NON SYSTEM is missing or corrupted and the database crashed, recovery can be performed after

the database is open. Pre requisites: A closed or open database backup and archived logs.

When startup database we would get ora-1157 & ora-1110and the name of the missing datafile, the

database will be remained in mount phase, then use OS command cpto restore the missing datafile

to its original location,

STEP 1 $cp -p /u03/coldbkp/rose/users01.dbf /u01/app/oracle/ordata/rose/

STEP 2 alter database datafile3 offline;

STEP 3 alter database open;

STEP 4 recover datafile 3;


In step 2 Tablespace name cannot be used because the database is not opened.

Complete Open Database Recovery

If a NON SYSTEM tablespace is missing or corrupted while the database is open, recovery can be

performed while the database is up and running. Pre requisites are, a closed or open database

backup and archived logs.

Use OS command cp to restore the missing or corrupted datafile to its original location.

STEP 1 $cp -p /u03/coldbkp/rose/users01.dbf /u01/app/oracle/oradata/rose/users01.dbf


STEP 3 recover tablespace ;


Restore &Recovery of a Datafile to a different location.

If a NON SYSTEM datafile is missing and its original location not available, restore can be made

to a different location and recovery performed. Pre requisites are all relevant archived logs.

Use OS commands to restore the missing or corrupted datafile to the new location.


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STEP 1 $ cp -p /u03/coldbkp/rose/users01.dbf /u02/app/oracle/oradata/rose/users01.dbf


STEP 3 alter tablespace rename datafile '/old_path/user01.dbf' to

'/new_path/users01.dbf';

STEP 4 recover tablespace ;STEP 5 alter tablespace online;

Control File Recovery

If control files are missing, database crash. Pre requisites: A backup of your control file and

all relevant archived logs. Database startup gives us (ora-205, missing controlfile, instance start

but database is not MOUNTED. Use OS command cp to restore the missing control file to its

original location:

STEP 1 $cp -p /u03/coldbkp/rose/*.ctl /u01/app/oracle/oradata/rose/

STEP 3 alter database mount;

STEP 4 recover automatic database using backup controlfile;

STEP 5 alter database open resetlogs;

NOTE:Take a new complete backup, as the database is open in a new incarnation and previous archived

log are not relevant.

Incomplete Recovery, Until Time/Sequence/Cancel

Incomplete recovery means when an archived log is missing, so recovery can only be made until the

previous sequence, or when an important object was dropped, and recovery needs to be made until

before the object was dropped.

Pre requisites are a closed or open database backup and archived logs, the timeor sequencethat

the 'until' recovery needs to be performed. If the database is open follow given steps,

STEP 1 shutdown abort;

Use OS command cp to restore all datafiles to its original locations:

STEP 2 $cp -p /u03/coldbkp/rose

STEP 3 startup mount;

STEP 4 recover automatic database until time '2014-01-31:14:40:45';

STEP 5 alter database open resetlogs;

NOTE:Take a new complete backup, as the database is open in a new incarnation and previous

archived log are not relevant. Alternatively we can use instead of until time, until sequence or

until cancel.

STEPS TO RECOVER SYSTEM TABLESPACE IS MISSING

If the system tablespace is missing or corrupted the database cannot be started up so a complete

closed database recovery must be performed. Pre requisites are a closed or open database backup

and archived logs.

Use OS command cp to restore the missing or corrupted system datafile to its original

location.


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STEP 1 $cp -p /u03/coldbkp/rose/system01.dbf /u01/app/oracle/oradata/rose/system01.dbf

STEP 2 startup mount;

STEP 3 recover datafile 1;

STEP 4 alter database open;

IF UNDO TABLESPACE BECOMES UNAVAILABLE

If you receive ORA-01110, follow given steps:

STEP 1 Startup your database in mount mode only.

STEP 2 Change the undo_management parameter to manual and bounce your database in mount mode again.

STEP 3 Drop the undo datafile using the offline option.

STEP 4 Open the database now.

STEP 5 Drop the Undo Tablespace.

STEP 6 Create a new undo tablespaceSTEP 7 Change the undo_management parameter to auto:

STEP 8 Bounce(restart)your database.

COLD BACKUP & RECOVERY SCENARIOS.pdf

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