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5 Operation : 5.2 Managing Backups Using a Retention Policy : 5.2.3 Setting the Retention Policy

The retention policy is determined by the retention_policy parameter in the BART configuration file. To set it globally for all servers, see Section 4.1. To set it by database server, see Section 4.2.5.
To use the redundancy retention policy, set retention_policy = max_number BACKUPS where max_number is a positive integer designating the maximum number of most recent backups.
The keyword BACKUPS must always be specified in plural form (for example, 1 BACKUPS).
BART will accept a maximum integer value of 2,147,483,647 for max_number, however, a realistic, practical value based on your system environment must always be used.
The redundancy retention policy is the default type of retention policy if all keywords BACKUPS, DAYS, WEEKS, and MONTHS following the max_number integer are omitted as shown by the following example:
The SHOW-SERVERS subcommand displays the 3 backup redundancy retention policy in the RETENTION POLICY field:
To use the recovery window retention policy, set the retention_policy parameter to the desired length of time for the recovery window in one of the following ways:
Set to max_number DAYS to define the start date/time recovery window boundary as the number of days specified by max_number going back in time from the current date/time.
Set to max_number WEEKS to define the start date/time recovery window boundary as the number of weeks specified by max_number going back in time from the current date/time.
Set to max_number MONTHS to define the start date/time recovery window boundary as the number of months specified by max_number going back in time from the current date/time.
The keywords DAYS, WEEKS, and MONTHS must always be specified in plural form (for example, 1 DAYS, 1 WEEKS, or 1 MONTHS).
BART will accept a maximum integer value of 2,147,483,647 for max_number, however, a realistic, practical value based on your system environment must always be used.
Invoking BART in debug mode (with the -d option) using the MANAGE subcommand with the -n option displays the calculated time length of the recovery window based on the retention_policy setting and the current date/time.
For example, using the following retention_policy settings:
If the MANAGE subcommand is invoked in debug mode along with the -n option on 2015-04-17, the following results are displayed:
For server acctg, 72 hours translates to a recovery window of 3 days.
For server dev, 504 hours translates to a recovery window of 21 days (3 weeks).
For server hr, 2160 hours translates to a recovery window of 90 days (3 months).
Note: For a setting of max_number MONTHS, the calculated, total number of days for the recovery window is dependent upon the actual number of days in the preceding months from the current date/time. Thus, max_number MONTHS is not always exactly equivalent to max_number x 30 DAYS. (For example, if the current date/time is in the month of March, a 1-month recovery window would be equivalent to only 28 days because the preceding month is February. Thus, for a current date of March 31, a 1-month recovery window would start on March 3.) However, the typical result is that the day of the month of the starting recovery window boundary will be the same day of the month of when the MANAGE subcommand is invoked.
Using the SHOW-SERVERS subcommand, the RETENTION POLICY field displays the start of the recovery window.
The start of the 3-day recovery window displayed in the RETENTION POLICY field is 2015-04-07 14:57:36 EDT when the SHOW-SERVERS subcommand is invoked on 2015-04-10.
At this current point in time, backups taken on or after 2015-04-07 14:57:36 EDT would be considered active. Backups taken prior to 2015-04-07 14:57:36 EDT would be considered obsolete except for backups marked as keep.
The start of the 3-week recovery window displayed in the RETENTION POLICY field is 2015-03-20 14:59:42 EDT when the SHOW-SERVERS subcommand is invoked on 2015-04-10.
At this current point in time, backups taken on or after 2015-03-20 14:59:42 EDT would be considered active. Backups taken prior to 2015-03-20 14:59:42 EDT would be considered obsolete except for backups marked as keep.
The start of the 3-month recovery window displayed in the RETENTION POLICY field is 2015-01-10 14:04:23 EST when the SHOW-SERVERS subcommand is invoked on 2015-04-10.
At this current point in time, backups taken on or after 2015-01-10 14:04:23 EST would be considered active. Backups taken prior to 2015-01-10 14:04:23 EST would be considered obsolete except for backups marked as keep.

5 Operation : 5.2 Managing Backups Using a Retention Policy : 5.2.3 Setting the Retention Policy

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