RMAN Cheat SHeet

Recovery Manager (RMAN)

-1-

RMAN can do everything a normal backup can do, however RMAN has its own backup catalog to record the backups that took place. The database can be in two formats archivelog mode or nonarchivelog mode • •

archivelog - Oracle saves the filled redo logs files, which means you can recovery the database to any point in time using the archived logs nonarchivelog - the redo logs are overwritten and not saved, but can only be recovery from the last backup.

There are several types of backup • • • • • •

whole backup - you backup the database as a whole which includes the controlfiles partial backup - you back only a part of the database such a tablespace, one data file consistent - a consistent backup does not need to go through recover when being restored, normally assiocated with a closed backup inconsistent - a inconsistent backup always needs to be recovered open - is backup taken when the database is running, also known as a hot, warm, online backup closed - is a backup taken when the database is shutdown also know as a cold, offline backup

The benefits to using RMAN are • • • • • • • •

Human error is minimized as RMAN keeps tracks of all the backups Simple command interface Unused block compression lets you skip unused data blocks, thus saving space and time. RMAN can be fully automated Can perform error checking when backing up or during recovery Can perform image copies which are simular to operating system backup Can be used with 3rd party backup management software like Veritas Netbackup It is well intergrated into OEM, so you can make use of Oracle's scheduler

RMAN Architecture RMAN operates via a server session connecting to the target database, it gets the metadata from the target, this is called the RMAN repository. The repository will contain information on • • • • •

Data file backup sets and copies Archived redo log copies and backup sets Tablespaces and data file information Stored scripts (only can be used if using a recovery catalog) RMAN configuration settings

The Recovery Catalog RMAN will use the controlfile on the target database to store repository information regarding any backups for that server, this information can also be stored in a recovery catalog (optional) which resides (on the target server) on its own database (default size should be about 115MB) on the target server or on a server dedicated to RMAN, information is still written to controlfile even if a recovery catalog is used.

Recovery Manager (RMAN)

-2-

The information stored in the controlfile is stored in the reusable sections called circular reuse records and noncircular reuse records. The circular reuse records have non-critical information that can be overwritten if needed. Some of the non-circular reuseable sections consists of datafiles and redo log information. RMAN can backup archive logs, controlfile, datafiles, spfile and tablespaces it does not backup temporary tablespaces, redo logs, password file, init.ora. The controlfile based repository will retain data for only the time specified by the instance parameter CONTROL_FILE_RECORD_KEEP_TIME this defaults to seven days. Media Management Layer If you backup to tapes you require additional software called MML (media management layer) or media manager. MML is a API that interfaces with different vendors tape libraries. RMAN terminology • • • • •

backup piece - operating system file containing the backup of a data file, controlfile, etc backup set - logical structure that contains one or more backup pieces, all relevant backup pieces are contained in a backup set image copy - simular to operating system copies like cp or dd, they will contain all block if if not used (disk only) proxy copy - media manger is given control of the copying process channel - Channel allocation is a method of connecting rman and the target database while also specifying the type of backup i.e. disk or tape, they can created manually or automatically.

Connecting to RMAN There are a number of ways to connect to RMAN and it depends on where the recovery catalog is c:\> set ORACLE_SID=D01 set the Oracle SID ORACLE_SID=D01; export ORACLE_SID connect to the target server use oracle_sid rman> connect target / and local controlfile connect the recovery manager catalog rman> connect catalog rman_user/password@d01 connect target & recovery manager catalog rman> connect target orcl catalog rman_user/password@d01 Configuring RMAN persistant settings RMAN’s persistent settings which are stored in the controlfile (reason why must be in mount mode) of the target database (#default means that parameter is at default setting) or a recovery catalog if used Displaying

rman> show all CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default CONFIGURE BACKUP OPTIMIZATION OFF; # default

Recovery Manager (RMAN)

-3-

CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default CONFIGURE CONTROLFILE AUTOBACKUP OFF; CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; CONFIGURE DEVICE TYPE DISK BACKUP TYPE TO COMPRESSED BACKUPSET PARALLELISM 1; CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT 'z:/orabackup/%U'; CONFIGURE MAXSETSIZE TO UNLIMITED; # default CONFIGURE ENCRYPTION FOR DATABASE OFF; # default CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default CONFIGURE SNAPSHOT CONTROLFILE NAME TO 'C:\ORACLE\PRODUCT\10.2.0\DB_1\DATABASE\SNCFD01.ORA';#default set default device to be a tape drive set default device to be a disk drive set default backup to be a image copy default disk backup to a compressed backupset (upto 20% ratio) default tape backup to a compressed backupset (upto 20% ratio) Set degree of parallelism Backup optimization My basic rman config

configure default device type to sbt; configure default device type to disk; configure device type disk backup type to copy;

configure device type disk backup type to compressed backupset;

configure device type sbt backup type to compressed backupset;

configure device type disk parallelism 4; configure device type sbt parllelism 4; configure backup optimization on; Note: this will ensure that RMAN does'nt perform a backup if it has already backed up identical versions. CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 30 DAYS CONFIGURE CONTROLFILE AUTOBACKUP ON CONFIGURE DEVICE TYPE DISK BACKUP TYPE TO BACKUPSET PARALLELISM 1 CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO 's:\ora_backup\controlfile_%F'

Recovery Manager (RMAN)

-4-

CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT 's:\ora_backup\ora_dev_f%t_s%s_s%p' SET CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO 's:\ora_backup\controlfile_%F'; Channel Parameters/Options The parameters/options are use to control the resources used by RMAN, there are many options probably best to consult the oracle documenation. • • • • • • •

channel device type - set default location of backups can be disk or sbt channel rate - limits i/o bandwith KB, MB or GB channel maxpiecesize - limits the size of the backup pieces channel maxsetsize - limits the size of the backup sets channel connect - instructs a specific instance to perform an operation duration - controls time for backup job (hours/mins) parms - send specific instructions to tape library

examples

rman> configure channel device type disk format ‘s:\ora_backup\ora_dev_f%t_s%s_s%p’; rman> configure channel device type disk rate = 5m; rman> configure channel device type disk maxpiecesize = 2g; rman> configure channel device type disk maxsetsize = 10g;

Backup Retention Default is redundancy 1 which means always attempt to have one backup image or backupset of every datafile, archive log and controlfile keep backups for 30 days rman> configure retention policy to recover window of 30 days; keep aleast 2 copies rman> configure retention policy to redundancy 2; reset back to 1 (default) rman> configure retention policy clear; extend the retention rman> change backupset tag monthly_backup keep until time ’01-dec-07’ logs; period Backup Tagging examples Format options

rman> backup database tag “monthly_backup”; rman> backup database as copy tag “monthly_backup”; You can use format options with backup commands to specify a location and name for backup pieces %F - combines database identifier (DBID), day, month, year and sequence number %U - Specifies a system generated unique filename (default) %u - specifies an 8 character name %d - name of database %s - backup set number

Recovery Manager (RMAN)

-5-

%t - backup set timestamp %p - piece number within the backup set Controlfile Backup rman> backup current controlfile; rman> configure controlfile autobackup on; (default location flash recovery area) examples rman> configure controlfile autobackup format for device type disk to ‘z:\orabackup\controlfile_%F’; Tablespace Excludes rman> configure exclude from tablespace test; (exclude test tablespace from backup) rman> configure exclude from tablespace test clear; (remove the exclude test tablespace from backup) rman> backup database noexeclude (ignore any exclude settings)

examples

Creating Backups rman> run { allocate channel c1 type disk; backup database format ‘db_%u_%d_%s’; (the backup set name for the data file) backup format ‘log_t%t_s%s_p%p’; (the backup set name from the archive logs) (archivelog all); }

Backup Sets

rman> run { allocate channel c1 type disk; allocate channel c2 type disk; backup (datafile 1,2,3 channel c1) (archivelog all channel c2); } rman> backup as compressed backupset database; rman> backup incremental level 0 database; - baseline incremental backup (a full backup ) rman> backup incremental level 1 database; - incremental backup must have baseline backup rman> backup incremental level 1 cumulative database; - backs up from last level 0 backup (NOT FULL) rman> backup as backupset copy of tablespace sysaux; (create a backupset from a image copy)

Backup Images rman> run { allocate channel c1 type disk;

Recovery Manager (RMAN)

-6-

copy datafile 1 to ‘z:\orabackup\system01.dbf’, current controlfile to ‘z:\orabackup\control01.ctl’; } rman> backup as copy database; rman> backup as copy copy of database; rman> backup copy as copy tablespace sysaux; rman> backup as copy datfile 2; rman> configure device type disk parallelism 3; (must have 3 channels) Parallel Streams

Other examples

Note : You only configure the number of streams to the number of channels, if you configure more they will not start. Remember that you need multiple channels configured to use the streams. rman> backup device type disk copies 2 datafile 1 format ''disk1/df1_%U', '/disk2/df1_%U'; rman> backup as copy copy of database from tag 'test' check logical tag 'duptest'; rman> backup database plus archivelog; rman> backup as copy duration 04:00 minimize time database; rman> backup as compressed backupset database plus archivelog; Note: logical - perform logical check of the backup files duration - time limit to perform the bacup minimise - perform the backup as fast as it can compressed - compress the backup set, remember it will take longer to recovery as it needs to uncompress

Validating/Cross Checking Backups You can validate a backup set before you restore which ensures that backup files exist in the proper locations and that they are readable and free from any logical and physical corruptions, you can also crosscheck backup sets to make sure they are available and have not been deleted (backup sets can be deleted from the operating system level). Validate a backup crosscheck

rman> validate backupset 1; rman> crosscheck backupset 1;

Viewing backups The v$ views information regarding backups is always located in the target database’s or target database’s controlfile. The list commands are used to determine files impacted by the change, crosscheck and delete commands. The report command is accurate when the control and RMAN repository are synchronised which can be performed by the change, crosscheck and delete commands list all image copies list all backups

rman> list copy; rman> list archivelog all; rman> list backup;

Recovery Manager (RMAN)

list backed up files list backed up databases; list all datafile number 1 backups list backed up controlfiles list backup scripts

-7-

rman> list backupset by backup [summary|verbose]; rman> list backupset by file; rman> list backup of database; rman> list backup of datafile 1; rman> list backup of controlfile; rman> list script names; rman> list global script names;

list all backups no longer required according to rman> report obsolete; retention policy list all the physical datafiles rman> report schema; list files that require backing up rman> report need backup Useful Tables v$backup_files lists each file backed up, also has compressed option v$backup_set lists backup sets v$backup_piece lists backup pieces v$backup_redolog lists archived backup logs v$backup_spfile lists spfiles v$backup_device names of SBT devices that have been linked to rman v$rman_configuration lists all changed configurations settings (good point to check config) v$rman_status Status of all completed rman jobs v$backup_corruption provides important corruption information v$copy_corruption provides important corruption information Deleting Backups To removed old archive logs use DELETE ALL INPUT, if all is missed only the archive logs in the primary destination will be deleted.

Examples

rman> delete backupset 12; rman> delete backupset tag=monthly_backup; rman> delete copy of datafile 6; rman> delete copy of archivelog all; rman> delete obsolete; Note: obsolete - delete all backups no longer needed due to retention levels

Catalog commands The catalog command helps you identify and catalog any files that aren't recorded in RMAN's repository and thus are known to RMAN

Recovery Manager (RMAN) catalog all data files copies catalog all backup pieces copies Search for uncatalog files in a directory Delete discrepancy in catalog

-8-

rman> catalog datafilecopy 'c:\oracle\backup\users01.dbf'; rman> catalog backuppiece ':c\oracle\backup\backup_20.bkp'; rman> catalog start with ':c\oracle\backup'; rman> delete force noprompt archivelog sequence 40;

Block change tracking Block change tracking is used to backup very large databases,when you enable change block tracking a new process CTWR is then started: Enabling Viewing Disabling

sql> alter database enable block change tracking using file ‘c:\oracle\tracking\block_tracking.log’ sql> select filename, status, bytes from v$block_change_tracking; sql> alter database disable block change tracking;