Choosing availability options

 

Availability options are complements to a good save strategy, not replacements. Availability options can significantly reduce the time that it takes you to recover after a failure. In some cases, availability options can prevent you from performing a recovery.

To justify the cost of using availability options, you need to understand the following items:

• The value that your system provides.

• The cost of a scheduled or an unscheduled outage.

• The type of your availability requirements.

The following list shows the availability options that you can use to complement your save strategy:

• Journal management enables you to recover the changes to objects that have occurred since your last complete save.

• Access path protection enables you to recreate the order in which records in a database file are processed.

• Disk pools limit the amount of data you need to recover to the data in the disk pool with the failed unit.

• Device parity protection enables you to reconstruct the data that is lost; the system can continue to run while the data is being reconstructed.

• Mirrored protection helps you keep your data available because you have two copies of the data on two separate disk units.

• Clustering enables you to maintain some or all data on two systems. The secondary system can take over critical application programs if the primary system fails.

 

Parent topic:

Planning a backup and recovery strategy

Related concepts
Availability roadmap

Related reference
Special values for the SAVLIB command