Acronis Backup & Recovery 10 Advanced Workstation TIDLBPDES5 Manual De Usuario

 

These options define the tape rotation scheme that is classical for GFS. The figure shows the 
beginning of the rotation scheme that uses 8 tapes for daily backups, 6 tapes for weekly backups and 
13 tapes for monthly backups (since there are 13 four-week cycles in a year) for the analyzed case. 
And one tape is required for the next backup. In total this rotation scheme, combined with the 
options requires 28 tapes. 

 

To recover the data only one tape is required for a full backup, two tapes for a differential backup, 
and two or three tapes for an incremental backup. 

This scheme has the following advantages: 

• 

access to any full backup requires only one tape 

• 

backup deletion frees a tape so it can be reused. 

The main drawback is the large number of required tapes that is used 5-10%. 

If we have to keep a daily backup for a week (4 backups) and a weekly backup for a month (4 
backups), the total number of required tapes will be equal to 4+4+13+1 = 22. 

 

Using the Tower of Hanoi tape rotation scheme 

The ToH scheme requires fewer tapes for rotation as compared with the GFS scheme. So the ToH 
scheme is the best choice for small tape libraries, especially for autoloaders. 

Once the ToH backup scheme is selected, it is possible to specify the scheme schedule and the 
number of levels. 

Best practice suggests that five levels should be used if you are applying the Tower of Hanoi to weekly 
backups and eight levels if you are applying it to daily backups. In the first case the rotation includes 

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