Rman can be used to back up and restore data files, control files, archive logs, etc. It can also be used as a completely and incomplete oracle recover tool. The command line or OEM bac rman can be used to backup and restore data files, control files, archive logs, and other oracle tools. It can also be used as a completely and incomplete recover oracle tool. It is controlled by the command line or the backup manager GUI of the OEM. RMAN is block-level backup and recovery.
Rman main components:
1) Target Database: (Target Database)
Target objects of rman
2) session
Sys @ ORCL> select sid, username, program from v $ session where username is not null;
SID USERNAME PROGRAM
------------------------------------------------------------
142 SYS rman@localhost.local
Domain (TNS V1-V3)
158 SYS rman@localhost.local
Domain (TNS V1-V3)
3) server process
[Oracle @ localhost ~] $ Ps-ef | grep oracle
Oracle 11721 11716 0? 00:00:00 oracleorcl (DESCRIPTION = (LOCAL = YES) (ADDRESS = (PROTOCOL = beq )))
Oracle 11722 11716 0? 00:00:00 oracleorcl (DESCRIPTION = (LOCAL = YES) (ADDRESS = (PROTOCOL = beq )))
At the beginning, rman starts two server processes by default to establish two sessions with the target database. Rman completes related work through sp.
4) channel)
The distribution channel is based on the device (SBT and DISK. The rman channel is essentially a data stream to the storage device.
5) recovery catalog :( Restore directory)
The database that stores rman metadata. It is better to be remote.
6) Media Management Layer
To back up data to a tape drive, you must configure the media management layer to use third-party tools, such as MML.
Rman terminology
1) Full backup Sets Full backup set
Back up used data blocks (Note: used, not modified)
2) Incremental backup sets Incremental backup set
Back up modified data blocks
3) composite backup
Generate a specified number of copies at a specified position
4) backup set and backup slice
The backup set is logically composed of one or more backup slices, which are physically composed of data files, control files, and archive logs.