Zero Downtime Backup solution for Oracle10g

Transcription

1 Storage Grid Seminar Oktober 2005 Frankfurt, München, Hamburg Zero Downtime Backup solution for Oracle10g Jaime Blasco HP/Oracle CTC (Cooperative Technology Center) EMEA Competence Center 2004 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice

2 Agenda Oracle Backup concepts Split/Mirror Backup Zero Downtime Backup / Instant Recovery for Oracle ZDB Live Demo

3 HP achieves world record backup and restore achieved with the following equipment: Superdome with 32CPU's XP1024 HP Tape library (ESL9595) with 16 Ultrium2 drives Oracle 9iR2 ( ) for recovery catalog and target database OpenView Data Protector TB/hr Oracle online backup 1.23TB/hr Oracle restore 4.3TB database on file system using the TPC-H standard setup: 8 tables partitioned over ~150 Tablespaces and ~ 260 datafiles.

4 The team

5 Oracle DB Backup and Recovery concepts Based on the status of the Oracle Server, the Backup can be: Offline Backup Online Backup Oracle distinguishes between: User Managed Backup: OS copy commands Server Managed Backup: RMAN (Recovery MANager)

6 Oracle DB Backup and Recovery concepts

7 Backup Methods Closed database Closed or open database Noarchivelog mode Archivelog mode Physical backup

8 Consistent Whole Database Backup (Closed Database Backup) Datafiles Control files Redo log files Parameter file Password file Online or offline storage

9 Open Database Backup Datafiles Control files Password file Parameter file Archived redo log files Online redo log files

10 Open Database Backup Options sql>alter tablespace users begin backup; sql>alter system begin backup; Tablespace USERS Tablespace USERS users01.dbf users02.dbf users01.dbf users02.dbf sql>alter tablespace users end backup; sql>alter system end backup;

11 Tablespace in backup mode When a tablespace is put into backup mode, the following three things happen: 2. Oracle checkpoints the tablespace, flushing all changes from shared memory to disk. 3. The SCN markers for each datafile in that tablespace are "frozen" at their current values. Even though further updates will be sent to the datafiles, the SCN markers will not be updated until the tablespace is taken out of backup mode. 4. Oracle switches to logging full images of changed database blocks to the redologs. Instead of recording how it changed a particular block (the change vector), it will log the entire image of the block after the change. This is why the redologs grow at a much faster rate while hot backups are going on.

12 Data Protector integration with Oracle Oracle 9i/10g server target database archive redo log control files recovery catalog Data Protector DP cell manager DP database data file data files tablespace 1 tablespace 2 RMAN channel C1 channel C2 channel C n API DP Oracle agent DP media agent DP media agent

13 Agenda Basic Oracle Backup Concepts Zero Downtime Backup / Instant Recovery concepts ZDB and Oracle10g Oracle ZDB live demo

14 tape hp is backup shifting focus no longer from backup meets the to recovery need for high-speed recovery within the past hour recovery point objective (how old is the data to which I recover?) within past 24 hours tape backup INSTANT RECOVERY several hours recovery time objective (how long does it take?) minutes Page 14

15 Faster data recovery methods low-cost disk recovery Advanced backup to disk management management application server application server backup server low-cost storage low-cost zero-downtime disk recovery backup application application server server productio n data management t backup server copy low-cost storage tape application server t production data low-cost storage Instant Recovery t 0 backup server tape management tape library recovery images recovery images on tape on disk

16 zero downtime backup process running environment O O O 1. The application writes data to the array, using RAID to control distribution of the data across physical disks. O O R snapshot/snapclone 4. snapshots / snapclones are taken. R O R 5. DB is taken out of Backup mode/put back on-line. backup session start O O O 2. Backup session starts. 3. DB is put into backup mode/offline. O O R backup session completion R O R 6. If a tape backup is specified, the snapshot of data is backed up to tape. 7. Backup session ends.

17 Zero Downtime Backup Key features Perfectly integrated into Data Protector Easily implement backup jobs without custom script development Use of Snapshots or Snapclones on the EVA array, BC or CA on the XP. Application is not impacted during the backup process A dedicated backup server runs the backup from the Snapshot/Snapclone or BC

18 Zero Downtime Backup snapshot backup concept for EVA Application host O O EVA R R Zero Downtime Backup Snapshots/snapclones can be created on the fly Backup host processes the data Snapshots/snapclones get removed at the end of the backup O - Original R - Replica Backup host

19 instant recovery concept (general) Tape restore approach Instant Recovery approach O O R original replica O R R all restores from tape restore to the application host (or backup host if disk array supports this) either host involved in data processing fast, automated restore directly from the replica minutes instead of hours no host involved in data processing

20 Instant Recovery for EVA Key features Builds on the ZDB solution Keeps a defined number of shadow copies on the EVA for fast recovery Recover your data in minutes rather than hours from tape Snapclone only Rotating copies for restore

21 instant recovery multiple version on disk Builds on zero-downtime backup to retain multiple images on disk for selective recovery to any point-in-time image. single scheduler, single recovery interface management tape library Data Protector fully automates the protection process, including creation and rotation of mirrors or snapshots. for recovery, administrator selects a specific recovery image from the graphical user interface application server production data t media agent recovery images on tape t 0 t -1 t - 2 recovery images on disk

22 replica storage snapshot / snapclone rotation Application server Production volume FC SAN replica storage: Snapshot, -clone in rotation catalog database: - files, versions, hosts - media, drives, libraries Backup server recovery images on tape replicas (snapshots or snapclones) are rotated the backup re-uses the oldest replica each time it runs only snapclones are used for Instant Recovery (recovers Tbytes of data in minutes from replica)

23 instant recovery on EVA (example) application host - RU2 is selected for instant recovery and becomes the original disk - original disk is removed application host OU OU RU2 RU1 RU3 RU1 RU3 RU1 RU3 RU2 EVA RU2 EVA before IR during IR after IR EVA OU Original Unit RUx Replica Unit x (snapclone)

25 Oracle ZDB integration steps check Oracle requirements Oracle file layout recovery catalog database required Net8 installed and configured whether Oracle is required on backup system depends on RMAN backup method install Data Protector components (disk array, Oracle) on application and backup server install Data Protector licenses configure the integration create backup specification perform backup / restore / instant recovery

26 Oracle setup Redo logs original units replica units Control files RMAN backup archive log RMAN online / offline thru application host (proxy copy) DMA on/offline Archive logs XP / VA / EVA Data files

27 Oracle RMAN: backup set proxy copy RMAN offers two types of backup methods: backup set and proxy copy Data Protector 5.5 supports proxy copy and backup set for Oracle ZDB up to Omniback 4.1: only backup set is supported data protector 5.0 & 5.1 supports only proxy copy (except with Oracle 8.0.x) whitepaper has introduced support for backups set ZDB for DP 5.1 (HP-UX) data protector 5.5 supports both Oracle backup user - managed proxy copy RMAN backup set

28 backup method: proxy copy what is proxy copy? media management vendor software (data protector) takes over data movement Oracle introduced proxy copy with version 8i (8.1.5) what does this mean to the DP ZDB integration? backup server doesn t require Oracle installation proxy copy returns a list of datafiles list of datafiles are copied via replica to the backup system datafiles are backed up on the backup server complete datafiles are backed up data protector 5.0 and 5.1 support only proxy copy for Oracle 8i/9i

29 backup method: backup set what is backup set? Oracle sends/receives (backup/restore) data streams to/from the media management backup tool RMAN specific format also called stream backup what does this mean to the Data Protector ZDB integration? backup server requires Oracle installation data files are copied via replica to the backup system Oracle instance is started on the backup server and backup is performed only used blocks are backed up

30 configuration backup method is determined when configuring the integration for proxy copy util_oracle8.exe CONFIG_SMB_PROXY <ORACLE_SID> Oracle SID <ORACLE_HOME> Oracle home directory <TARGET_DATABASE_LOGIN> connection string target db <RECOVERY_CATALOG_LOGIN> connection string catalog db <CONTROL_FILE_LOCATION> location for backup control file for backup set util_oracle8.exe CONFIG_SMB_BACKUP_SET <ORACLE_SID> Oracle SID <ORACLE_HOME> Oracle home directory <TARGET_DATABASE_LOGIN> connection string to target db <RECOVERY_CATALOG_LOGIN> connection string to catalog db <CONTROL_FILE_LOCATION> location for backup control file

31 create backup specification combination of normal oracle integration and disk array parameters 1. select split mirror or snapshot backup 6. select disk array options 7. select oracle backup options

32 overall procedure of a IR/Roll Forward 1. Oracle database has to be manually shut down 2. IR/roll forward is started via DP GUI all Oracle data files get restored caused by a resync from the replica to the original unit DP creates RMAN script according the user specified options RMAN script is started to recover the database missing archive logs and/or incremental backups are restored automatically by RMAN recovery is done until the specified time most recent time (now), specified time, logseq/thread, system change number (SCN) opens the database (optionally)

33 Instant Recovery options

35 LIVE DEMONSTRATION OF ZERO DOWNTIME BACKUP AND INSTANT RECOVERY!

36 Demo environment for ZDB/IR Application Host hp-ux SAN DP Cell Server w2k LAN oracle2 oracle3 OU OU EVA RU RU BACKU P OU: original unit RU: replica unit SAN Backup Host hp-ux oracle1

37