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Home -> Community -> Usenet -> c.d.o.server -> Re: problem with RMAN
The recovery catalog
From the Oracle8 Server Backup & Recovery Guide '..the recovery catalog is a repository of information that is used and maintained by RMAN. RMAN uses the information in the recovery catalog to determine how to execute requested backup and restore actions..'.
The recovery catalog can be in a schema of an existing Oracle8 database. However if RMAN is being used to backup multiple databases, it is probably
worth creating a dedicated recovery catalog database. THE RECOVERY
CATALOG
DATABASE CANNOT BE USED TO CATALOG BACKUPS OF ITSELF.
The Oracle8 Server Backup & Recovery Guide p.6-3 lists typical space
requirements for the recovery catalog.
To set up the recovery catalog, firstly ensure that catalog and catproc have been run, then execute the following:
SVRMGR> spool create_rman.log
SVRMGR> connect internal
SVRMGR> create user rman identified by rman
temporary tablespace temp
default tablespace rcvcat quota unlimited on rcvcat;
SVRMGR> grant recovery_catalog_owner to rman;
SVRMGR> connect rman/rman
SVRMGR> @?/rdbms/admin/catrman
Check create_rman.log for errors. The above commands assume that the TEMP and RCVCAT tablespaces have been created.
Also ensure that catproc has been run on the target database; RMAN makes extensive use of RPCs.
It is very important that the recovery catalog database is backed up regularly and frequently.
Note: Although you are not required to use a recovery catalog with RMAN, it is recommended. Because most of the information in the recovery catalog
is available via the target database's controlfile, RMAN can use this information for recovery purposes. For more information and limitations on using RMAN without a recovery catalog, please see the Oracle8 Server Backup & Recovery Guide pp.7-8, 7-8.
Starting RMAN
RMAN has a command line interface, or can be run from Enterprise Manager. For the purposes of this document, only the CLI will be covered.
For the purposes of the following examples, assume that
o. the target database is called "targdb" and has the same TNS alias o. "targdba" has been granted SYSDBA privileges o. the recovery catalog database is called "rcat" and has the same TNSalias
o. the schema containing the recovery catalog is "rman" (same password)
Before invoking RMAN, set the NLS_DATE_FORMAT and NLS_LANG environment variables. Much of the RMAN LIST output is date/time related. It is often necessary to have this information displayed as accurately as possible when performing time-based recovery. Example NLS settings:
NLS_LANG=AMERICAN_AMERICA.WE8ISO8859P1
NLS_DATE_FORMAT=DD-MON-YYYY HH24:MI:SS
For RMAN to connect to the recovery catalog and the target database, the recovery catalog database must be OPEN, while the target instance must be at least STARTED. If not, RMAN will give an error. To perform backups with
the target database open, the target MUST be in archivelog mode.
Connecting to RMAN without a recovery catalog
Set ORACLE_SID to be the target database, and issue the following:
% rman nocatalog
RMAN> connect target
or if the target database uses a password file,
RMAN> connect target targdba/<password>@targdb
Connecting to RMAN with a recovery catalog
% rman rcvcat rman/rman_at_rcat
RMAN> connect target
or if the target database uses a password file,
% rman rcvcat rman/rman_at_rcat target targdba/<password>@targdb
Using RMAN
Once connected to the target database, you can specify RMAN commands
either interactively or by using stored scripts. An example of
using RMAN interactively would be:
RMAN> resync catalog;
An example of calling a stored script would be:
RMAN> execute script alloc_1_disk;
To create/replace a stored script:
RMAN> replace script alloc_1_disk
2> allocate channel d1 type disk;
3> }
Register the target database
Database status:
Recovery catalog: open
Target: mounted or open
The target database must be registered with the recovery catalog before using RMAN against the database for the first time:
RMAN> register database;
Adding existing backups to the recovery catalog
Database status:
Recovery catalog: open
Target: mounted or open
If user-created backups existed under version 8.x prior to registering with
the target database, these can be added to the recovery catalog as follows:
RMAN> catalog datafilecopy '/supp/ .... /systargdb.dbf';
To view this file in the catalog, use the following command:
RMAN> list copy of database;
Backing up in noarchivelog mode
Database status:
Recovery catalog: open
Target: instance started or database mounted
Recovery catalog database is OPEN, target database is started (optionally mounted). Because the target database is not in archivelog mode, it must not be open when performing backups of datafiles. This would be equivalent
of making filesystem copies of datafiles without putting tablespaces into hot backup mode. If the database is open and not in archivelog mode, RMAN will generate an error when you attempt to perform a datafile backup
Example of how to back up a complete database
RMAN> run {
2> # backup the complete database to disk
3> allocate channel dev1 type disk;
4> backup
5> full
6> tag full_db_sunday_night
7> format '/oracle/backups/db_t%t_s%s_p%p'
8> (database);
9> release channel dev1;
10> }
Line#
2: Comment line (anything after the '#' is a comment)
3&9: See section 15 - Channels
5: Full backup (default if full or incremental not specified)
6: Meaningful string (<=30 chars)
7: Filename to use for backup pieces, including substitution
variables.
Oracle8 Backup & Recovery Guide p8-26 explains these variables
8: Indicates all files including controlfiles are to be backed up
To view this backup in the catalog, use the following command:
RMAN> list backupset of database;
Example of how to back up a tablespace
RMAN> run {
2> allocate channel dev1 type disk;
3> backup
4> tag tbs_users_read_only
5> format '/oracle/backups/tbs_users_t%t_s%s'
6> (tablespace users);
7> release channel dev1;
10> }
Line#
6: Specifying only the USERS tablespace for backup
To view this tablespace backup in the catalog, use the following
command:
RMAN> list backupset of tablespace users;
If for example the USERS tablespace is going to be put READ ONLY after
being backed up, subsequent full database backups would not need to
backup this tablespace. To cater for this, specify the 'skip readonly'
option in subsequent backups.
Note that although this is a tablespace backup, the target database
does NOT have to be open, only mounted. This is because tablespace
information is stored in the controlfile in o8.
Example of how to backup individual datafiles
RMAN> run {
2> allocate channel dev1 type 'SBT_TAPE';
3> backup
4> format '%d_%u'
5> (datafile '/oracle/dbs/sysbigdb.dbf');
6> release channel dev1;
7> }
Line#
2: Allocates a tape drive using the media manager layer (MML)
Note that no tag was specified and is therefore null.
To view this tablespace backup in the catalog, use the following
command:
RMAN> list backupset of datafile 1;
Copying datafiles
RMAN> run {
2> allocate channel dev1 type 'SBT_TAPE';
3> copy datafile '/oracle/dbs/temp.dbf' to
'/oracle/backups/temp.dbf';
4> release channel dev1;
5> }
To view this file copy in the catalog, use the following command:
RMAN> list copy of datafile '/oracle/dbs/temp.dbf';
Copying a datafile is different to backing up a datafile. A datafile
copy
is an image copy of the file. A backup of the file creates a
backupset.
Backing up the controlfile
RMAN> run {
2> allocate channel dev1 type 'SBT_TAPE';
3> backup
4> format 'cf_t%t_s%s_p%p'
5> tag cf_monday_night
6> (current controlfile);
7> release channel dev1;
8> }
Note that a database backup will automatically back up the
controlfile.
Backing up in archivelog mode
Database status:
Recovery catalog: open
Target: instance started, database mounted or open
The commands are identical to those in section 7 except that the target database is in archivelog mode.
Backing up archived logs
The following script backs up all archive logs:
RMAN> run {
2> allocate channel dev1 type disk;
3> backup
4> format '/oracle/backups/log_t%t_s%s_p%p'
5> (archivelog all);
6> release channel dev1;
7> }
The following script backs up archive logs from sequence# 90 to 100:
RMAN> run {
2> allocate channel dev1 type disk;
3> backup
4> format '/oracle/backups/log_t%t_s%s_p%p'
5> (archivelog from logseq=90 until logseq=100 thread 1);
6> release channel dev1;
7> }
The following script backs up all archive logs generated in the past
24 hours. Furthermore it actually deletes the logs after backing them
up. If the backup fails, logs will NOT be deleted:
RMAN> run {
2> allocate channel dev1 type disk;
3> backup
4> format '/oracle/backups/log_t%t_s%s_p%p'
5> (archivelog from time 'sysdate-1' all delete input);
6> release channel dev1;
7> }
To view the archive logs in the catalog, use the following command:
RMAN> list backupset of archivelog all;
Note that RMAN will backup specified logs if it finds them. If it
can't
find a log, it does not issue a warning.
Backing up the online logs
Online logs CANNOT be backed up using RMAN; they must be archived first.
To do this, you can issue SQL commands from RMAN e.g.
RMAN> run {
2> allocate channel dev1 type disk;
3> sql "alter system archive log current";
4> backup
5> format '/oracle/backups/log_t%t_s%s_p%p'
6> (archivelog from time 'sysdate-1' all delete input);
7> release channel dev1;
8> }
The above script might be run after performing a full 'database open'
backup. It would ensure that all redo to recover the database to a
consistent state would be backed up.
Note, you cannot tag archive log backupsets.
As can be seen from an earlier example, it is possible to direct an SMR
server session to delete archived redo logs once they have been backed
up. This option should obviously be used with extreme caution! Only
ever delete archivelogs if you are 100% satisfied that you have good
copies/backups elsewhere.
18.3. Keep it simple
As with all backup & recovery strategies, they should be as simple as
possible, and should be tested thoroughly.
A few simple stored scripts should be adequate for the vast majority
of backup & recovery requirements.
18.4. RMAN errors
When RMAN goes wrong it's spectacular! The error stacks are usually
very long. If an error is reported, it is worth getting the complete
stack sent to support as most of the errors will not help in
diagnosing
the problem.
"The Views expressed here are my own and not necessarily those of Oracle Corporation"
Norman Mueller <nm_at_berlin.snafu.de> wrote in message news:38408919.E640355B_at_berlin.snafu.de...
> Hello,
>
> I want to setup rman for backup and recovery. The problem is that I
> can't start
> it on our Solaris box. We use Oracle 8.0.5. I always get the following
> message:
>
> RMAN-00569: ================error message stack follows================
> RMAN-00552: syntax error in command line arguments
> RMAN-01005: syntax error: found "identifier": expecting one of:
> "allocate,
> beginline, catalog, change, connect, create,
> delete, exit, endinline, host, {, library, list, print, register,
> release,
> replace, report, reset, resync, rman, rpctest
> , run, set, sql, test"
> RMAN-01008: the bad identifier was: rman
> RMAN-01007: at line 2 column 1 file: command line arguments
>
> I have tried to start rman with and without command line arguments but
> the
> result is always the same. Does anyone know why????
>
> thanx for your help.
Received on Sun Nov 28 1999 - 00:02:11 CST
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