2.5

Backup Strategies
Backup strategies center on your business requirements for protecting your data. Database backup strategies
vary according to business requirements and the database environment, such as production, development, or
QA.
For example, for a production database with a high transaction volume and business rules that require the
highest possible database resiliency, you might define the following backups:
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Take full external backups twice a day.
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Take database snapshots every hour.
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Enable point-in-time recovery to keep a continuous log of all transactions as they occur on the running
database.
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Retain your full backups for a month or more.
If your business rules state that you must preserve every transaction, you can specify that the database must
shut down if the point-in-time recovery's write-ahead log runs out of space. For a development database where
data loss is not a concern, you might take full external backups every week with daily snapshot backups and
point-in-time recovery disabled.
You can initiate backups manually (one-time backups) or automatically (recurring backups). Backup methods
are snapshots and external (full database backup). You can enable point-in-time recovery. Depending on your
business rules, you can set up automated backups and use a combination of backup methods to safeguard
data.
You set up automated backups by attaching a database backup template to your database. Backup templates
contain backup and recovery settings. You can select a database backup template during database creation or
attach a template at a later time. You can also attach a different backup template at any time. If you have
sufficient privileges, you can modify the template settings or create custom backup templates. The backup
process picks up the latest settings the next time it runs. The modified settings do not affect backups that are
in progress.
Using database backup templates ensures that you can take consistent database backups, meet recovery goals,
and enforce your business rules. Data Director provides preconfigured database backup templates that provide
a range of backup and recovery settings. If you are not sure how much storage your backups will require, start
with the most conservative settings. You cannot decrease the backup storage allocation, but you can increase
it. Monitor the database activity and the backup size until you have a good idea of the workload and backup
space needed, and then adjust the storage amount.
Backup Types
You manage backups and recover data using Data Director snapshot backups, external backups, and point-
in-time recovery.
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External Backups on page 131
External backups are full copies of the database saved to a datastore separate from the database. This
section describes the pros and cons of using external backups.
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Snapshot Backups on page 131
Snapshot backups capture the changes to the database after the snapshot is taken. Snapshots initially use
less storage than external backup files and take just a few minutes regardless of database size.
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Point-In-Time Recovery on page 131
If point-in-time recovery (PITR) is enabled, a write-ahead log (WAL) continuously records every change
made to the database while the database is running. In the event of a failure, you can replay the WAL to
restore the database to its state at a point in time within the retention period of the database backups.
VMware vFabric Data Director Administrator and User Guide
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