Acronis Backup & Recovery 10 Adv WS TIDLBPDES Manuale Utente

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If your backup archive must provide recovery with daily resolution for the last several days, weekly 
resolution for the last several weeks and monthly resolution for any time in the past, the most 
preferred scheme for you is the Grandfather-Father-Son scheme. 
If the main goal is to provide data protection for the longest period with the minimal number of used 
tapes permanently loaded into a small tape library (e.g. autoloader), the best solution is to probably 
choose the Tower of Hanoi scheme. 
The Custom backup scheme enables you to specify a backup schedule and retention rules to define a 
desired tape rotation. Use this scheme, when the Grandfather-Father-Son and the Tower of Hanoi 
schemes’ usage is not enough. For example, if the full size of protected data is considerably less than 
the size of a tape, the best choice is to use the Custom  backup scheme with regular 
daily/weekly/monthly full backups, some simple retention rules, and tape options by default. 
 
Criteria of the choice 
Every time you are about to design a tape rotation scheme for a backup policy/plan to be created, 
you ought to come from the following arguments: 
• 
full size of the data to protect 
• 
approximate size of the daily changes of data 
• 
approximate size of the weekly changes of data 
• 
requirements for the backup scheme (frequency, performance and duration of backup 
operations) 
• 
requirements for keeping backups (minimal/maximal period of backup keeping; need to store 
tape cartridges off-site) 
• 
capability of the tape library (number of drives, loaders, slots and available tapes; capacity of 
tapes) 
• 
requirements for performing data recovery (maximal duration) 
You need to analyze every argument that is relevant for your case and select the main criteria for the 
choice. Then choose a backup scheme and specify the tape options. 
Note, that any backup scheme in combination with different tape options will have quite different 
results for efficient use of both tapes and devices. 
 
Case to analyze 
Suppose you need to automate a tape rotation for the case if: 
• 
the full size of the data to protect is approximately 320 GB 
• 
the approximate size of daily changes of data is about 16 GB 
• 
the approximate size of weekly changes of data is no more than 40 GB 
• 
tape capacity is 400 GB. 
Let’s analyze the results of a combination of GFS and ToH schemes with different tape options for the 
case. 
All the below analyzed examples are a simplistic approach to a real case, but provide you with a 
general conception of backup distribution onto tapes. 
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