RMAN COLD BACKUP BASIC
Basic explanation of
COLD BACKUP and HOT BACKUP
A database is in
CONSISTENT STATE when it shut down normally .
If database ARCHIVING
is not enabled(NOARCHIVELOG) you must take a CONSISTENT backup
A database is in
INCONSISTENT STATE when it is open and there are ongoing transactions AND it is
shutdown abnormally .
If database ARCHIVING
is enabled(NOARCHIVELOG) you take an INCONSISTENT backup.
A HOT
BACKUP is one that is taken when database is OPEN and is possible only if the
database is in ARCHIVELOG mode.
(PROBLEM)---HOT BACKUPS are performed at TABLESPACE level
only.
EXAMPLE
SQL>ALTER TABLESPACE USERS BEGIN
backup;
SQL> host cp /u01/app/oracle/oradata/orcl/users01.db /home/oracle/hotbackup
SQL> host cp /u01/app/oracle/oradata/orcl/users02.db
/home/oracle/hotbackup
SQL>ALTER TABLESPACE USERS END BACKUP;
---Next, force a log switch so Oracle will archive the current redo
log file.(for redo generated during the backup)
SQL>Alter system switch logfile;
Backup the CONTROL
FILE using the following command:
alter database backup controlfile to 'file_name';
-------------A COLD
BACKUP is taken when database is CLOSED and is possible in both NOARCHIVELOG
and ARCHIVELOG mode.
a))) To take a COLD BACKUP,database must be
shutdown in a consistent manner.....by issuing one
of the following commands:
1)shutdown normal
2)shutdown
transactional
If the database is
shutdown with the IMMEDIATE or ABORT option, it should be restarted in RESTRICT
mode and then shutdown with the NORMAL option.
b))) DETERMINE LOCATIONS (while database is
startup)
SQL> select value from v$parameter where name = 'spfile';
SQL> select name from v$controlfile;
SQL> select name from v$datafile;
After shutting down
the database,copy the DATAFILES,CONTROL FILES,REDO LOG FILES, PASSWORD FILE and
PARAMETER FILE of the database to your backup device using os 'copy' command.
c))) start up the database..
NEVER FORGET TO COMMENT..:)
Comments
Post a Comment