navigating the oracle backup maze
Skip this Video
Download Presentation
Navigating the Oracle Backup Maze

Loading in 2 Seconds...

play fullscreen
1 / 13

Navigating the Oracle Backup Maze - PowerPoint PPT Presentation

  • Uploaded on

Navigating the Oracle Backup Maze. Robert Spurzem Senior Product Marketing Manager [email protected] Agenda. How important is backup speed? RAW vs. cooked? Logical backups using Export utility RMAN vs. Alter Tablespace? Offline vs. online? Full vs. incremental? Snapshots?

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Navigating the Oracle Backup Maze' - aspen

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
navigating the oracle backup maze
Navigating the Oracle Backup Maze

Robert Spurzem

Senior Product Marketing Manager

[email protected]

  • How important is backup speed?
  • RAW vs. cooked?
  • Logical backups using Export utility
  • RMAN vs. Alter Tablespace?
  • Offline vs. online?
  • Full vs. incremental?
  • Snapshots?
  • Backup to Disk?
  • Future Trends
how important is backup speed
How important is backup speed?
  • Speed is important to meet the backup window
  • Speed is dependent on network bandwidth, devices and cpu
  • Vendor benchmarks aren’t real world configurations
  • Oracle RMAN is not the bottleneck
  • Databases greater than 200G – media servers are recommended
  • Restore needs to be tested for speed
    • 50G can take over 20 hrs if device and operational problems occur
raw vs cooked
RAW vs. cooked?
  • This is an application decision
  • RAW is fast but requires more management
  • File systems have more overhead but are easier to manage and backup
    • VxFS Quick I/O product has advantages
  • Makes no difference to RMAN
    • RMAN backs up from RAW or Cooked
    • RMAN restores from RAW or Cooked
    • RMAN can restore from RAW to Cooked or from Cooked to RAW
logical backups using export utility
Logical backups using Export utility
  • Export utility is provided with Oracle database and is easy to use
    • Does not require purchase of a module or agent product
  • Export examines every data block for consistency
  • Export backs up to disk so recovery can be fast
    • Export can restore by table within a tablespace
    • Can only recovery to a single point-in-time
  • Export takes longer than a physical backup
  • Full Export requires database to be in RESTRICT mode for intertable consistency
    • No database access during backup
rman vs alter tablespace
RMAN vs. Alter Tablespace?
  • ALTER TABLESPACE BEGIN online backup
    • Custom scripting required
    • Issue with fractured blocks
    • Freezes the data file header
    • Records the end of backup in the SCN header
    • Forces redo logs with recovery from the time of the backup
    • The redo logs fill faster with the full block changes, not the vector changes
    • Archiving means the online redo logs will continue to fill and archive logs will be used – must manage disk space.
rman vs alter tablespace7
RMAN vs. Alter Tablespace?
  • RMAN online backup
    • Introduced with Oracle 8
      • Five years of improvements
      • 50% use and growing
    • No fractured block issue
      • Reads the Oracle block size not the file system block size
      • Normal operation for redo logs
    • Reduces complexity
    • Efficient backup to tape
    • Multiple device streaming
    • Improvements with Oracle9i R2
      • Persistent Parameter Configuration
      • Restartable backup and restore
      • Self Describing Backup
offline vs online backups
Offline vs. online backups?
  • All depends on the db usage and activity
    • Can you shut down the db and for how long?
  • Can the backup be completed within the backup window?
  • No database access during offline backup
  • Database server is burdened with two processes during online backup
  • Archive log space management is required during online backup if the database is archiving
full vs incremental backups
Full vs. incremental backups?
  • Full Oracle backups are the norm no question
    • Perform full backups once a day
    • Backup the archive redo log files every 4 hours
  • Incremental backups performed by RMAN have well known deficiencies
  • Incrementals read the entire database to find the changed blocks
  • Incrementals have a difficult time streaming the tape device
are you a candidate for snapshots
Are you a candidate for snapshots?
  • What is a snapshot?
    • Frozen image backup from physical mirror or logical snapshot
  • Do you require fast recovery? (<2 hours)
  • Does your database need to be up 24x7; 80% utilization; no backup window
  • For very large databases >500G that are larger than backup window
  • RMAN Proxy Backup API
  • Array based vs. host based snapshots?
  • Are snapshots more complex?
are you a candidate for backup to disk
Are you a candidate for backup to disk?
  • The cost of disk is dropping
    • $1M/TB -> $100K/TB -> $10K/TB -> $1K/TB
    • New ATA drives are the driving factor
  • What are the advantages of backing up to disk?
    • Faster backup and faster recovery
  • What are the disadvantages?
    • Adds a second backup process
  • Tape backup still required for disaster recovery and archival
  • Adds potential complexity and management overhead
  • Potential for longer recovery times from tape
    • Single-step vs. Two-step recovery
future trends
Future trends
  • Full data life cycle management
    • Automation of entire information protection
    • Using snapshots; disk backup; tape archiving
    • Snapshot management
  • Efficient block level data protection
    • Faster backups and restores
    • Reduce media costs
  • Ease of management
    • Wizards to speed configuration and guide recovery
    • Automatic performance tuning