Oracle® Database Backup and Recovery Reference 10g Release 2 (10.2) Part Number B14194-03 |
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Syntax
reset::=
Purpose
To reset the incarnation of the target database in the RMAN repository, which means to do either of the following actions:
Inform RMAN that the SQL statement ALTER
DATABASE
OPEN
RESETLOGS
has been executed and that a new incarnation of the target database has been created. Note that if you run the RMAN command ALTER DATABASE OPEN
RESETLOGS
(not the SQL statement with the same keywords), then RMAN resets the target database automatically so that you do not have to run RESET
DATABASE
. By resetting the database, RMAN considers the new incarnation as the current incarnation of the database.
To reset the database to a previous incarnation. Typically, you would reset the incarnation when performing incomplete recovery to a point before a RESETLOGS
operation, or when attempting to undo the affects of a RESETLOGS
by restoring backups taken before a RESETLOGS
.
Restrictions and Usage Notes
Execute RESET
DATABASE
only at the RMAN prompt.
You must be connected to the target database.
A recovery catalog connection is optional. Unlike in catalog mode, RESET
DATABASE
in nocatalog mode changes the incarnation only for the current RMAN session.
You must issue a RESET
DATABASE
command before you can use RMAN with a target database that has been opened with the SQL statement ALTER
DATABASE
OPEN
RESETLOGS
option. If you do not, then RMAN refuses to access the recovery catalog because it cannot distinguish between a RESETLOGS
operation and an accidental restore of an old control file. The RESET
DATABASE
command informs RMAN that you issued a RESETLOGS
command.
If RMAN is connected NOCATALOG
, then you can only specify TO
INCARNATION
if the database is mounted and the control file contains a record of the prior incarnation. If you do not run RESET
DATABASE
, RMAN recovers to the last incarnation recorded in the control file.
If RMAN is connected in CATALOG
mode, then you can specify TO
INCARNATION
when the database is mounted. If database is mounted, however, then the control file must have a record of the prior incarnation.
Keywords and Parameters
Syntax Element | Description |
---|---|
TO INCARNATION primary_key |
Changes the current incarnation to an older incarnation. Specify the primary key of the DBINC record for the database incarnation. Run LIST INCARNATION OF DATABASE to obtain possible key values. After you issue RESET DATABASE TO INCARNATION , then you can run RMAN commands such as RESTORE and RECOVER . |
Examples
Resetting RMAN to a Previous Incarnation in NOCATALOG Mode: Example In NOCATALOG
mode, you must mount a control file that knows about the incarnation that you want to recover. The following scenario makes an old incarnation of database trgt
current again:
CONNECT TARGET / NOCATALOG # step 1: start and mount a control file that knows about the incarnation to which # you want to return. if the current control file does not know about it, then # you must restore an older control file STARTUP NOMOUNT; RESTORE CONTROLFILE UNTIL TIME 'SYSDATE-250'; ALTER DATABASE MOUNT; # step 2: obtain the primary key of old incarnation LIST INCARNATION OF DATABASE trgt; List of Database Incarnations DB Key Inc Key DB Name DB ID STATUS Reset SCN Reset Time ------- ------- -------- ------------- ------- ---------- ---------- 1 2 TRGT 1334358386 PARENT 154381 OCT 30 2001 16:02:12 1 116 TRGT 1334358386 CURRENT 154877 OCT 30 2001 16:37:39 # step 3: in this example, reset database to incarnation key 2 RESET DATABASE TO INCARNATION 2; # step 4: restore and recover the database to a point before the RESETLOGS RESTORE DATABASE UNTIL SCN 154876; RECOVER DATABASE UNTIL SCN 154876; # step 5: make this incarnation the current incarnation and then list incarnations: ALTER DATABASE OPEN RESETLOGS; LIST INCARNATION OF DATABASE trgt; List of Database Incarnations DB Key Inc Key DB Name DB ID STATUS Reset SCN Reset Time ------- ------- -------- ---------------- ------- ---------- ---------- 1 2 TRGT 1334358386 PARENT 154381 OCT 30 2001 16:02:12 1 116 TRGT 1334358386 PARENT 154877 OCT 30 2001 16:37:39 1 311 TRGT 1334358386 CURRENT 154877 AUG 13 2002 17:17:03
Resetting the Database After Incomplete Recovery: Example
This example assumes that an incomplete recovery or recovery with a backup control file was performed in NOCATALOG
mode. Later, RMAN is started in CATALOG
mode, but the RESYNC
command fails because the incarnation has not been reset in the catalog.
% rman target / catalog rman/rman@catdb Recovery Manager: Release 10.1.0.2.0 - Production Copyright (c) 1995, 2003, Oracle. All rights reserved. connected to target database: TRGT (DBID=1334531173) connected to recovery catalog database RMAN> RESYNC CATALOG; RMAN-00571: =========================================================== RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03009: failure of resync command on default channel at 11/01/2001 12:00:43 RMAN-20003: target database incarnation not found in recovery catalog RMAN> RESET DATABASE; new incarnation of database registered in recovery catalog starting full resync of recovery catalog full resync complete