Acronis Backup & Recovery 10 Advanced Workstation TIDLBPDES5 Manuale Utente

 

specify the sessions on which the scheme should run. In the discussion below, 
"days" can be replaced with "scheduled sessions". 

Number of levels 

Select from 2 to 16 backup levels. See the example stated below for details. 

Roll-back period 

The guaranteed number of sessions that one can go back in the archive at any 
time. Calculated automatically, depending on the schedule parameters and the 
numbers of levels you select. See the example below for details. 

Schedule parameters are set as follows 

• 

Recur: Every 1 day 

• 

Frequency: Once at 6 PM 

Number of levels: 4 

This is how the first 14 days (or 14 sessions) of this scheme's schedule look. Shaded numbers denote 
backup levels. 

1 2 3 4 5 6 7 8 9 10 

11 

12 

13 

14 

4 

1 

2 

1 

3 

1 

2 

1 

4 

1 

2 

1 

3 

1 

Backups of different levels have different types: 

• 

Last-level (in this case, level 4) backups are full; 

• 

Backups of intermediate levels (2, 3) are differential; 

• 

First-level (1) backups are incremental. 

A cleanup mechanism ensures that only the most recent backups of each level are kept. Here is how 
the archive looks on day 8, a day before creating a new full backup. 

1 2 3 4 5 6 7 8 

4 

1 

2 

1 

3 

1 

2 

1 

The scheme allows for efficient data storage: more backups accumulate toward the current time. 
Having four backups, we could recover data as of today, yesterday, half a week, or a week ago. 

The number of days we can go back in the archive is different on different days. The minimum 
number of days we are guaranteed to have is called the roll-back period. 

The following table shows full backup and roll-back periods for schemes of various levels. 

2 

2 days 

1 to 2 days 

1 day 

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