User`s guide

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Here, daily incremental backups will be created on Tuesdays and Thursdays, with weekly and
monthly backups performed on Fridays. Note that, in order to choose Friday in the Weekly/monthly
field, you need to first select it in the Back up on field.
Such an archive would allow you to compare your financial documents as of the first and the last day
of work, and have a five-year history of all documents, etc.
No daily backups
Consider a more exotic GFS scheme:
 Start backup at: 12:00 PM
 Back up on: Friday
 Weekly/monthly: Friday
 Keep backups:
 Daily: 1 week
 Weekly: 1 month
 Monthly: indefinitely
Backup is thus performed only on Fridays. This makes Friday the only choice for weekly and monthly
backups, leaving no other date for daily backups. The resulting “Grandfather-Father” archive will
hence consist only of weekly differential and monthly full backups.
Even though it is possible to use GFS to create such an archive, the Custom scheme is more flexible in
this situation.
7.3.7.5 Tower of Hanoi scheme
At a glance
 Up to 16 levels of full, differential, and incremental backups
 Next-level backups are twice as rare as previous-level backups
 One backup of each level is stored at a time
 Higher density of more recent backups
Parameters
You can set up the following parameters of a Tower of Hanoi scheme.
Schedule Set up a daily (p. 160), weekly (p. 162), or monthly (p. 164) schedule. Setting up
schedule parameters allows creating simple schedules (example of a simple daily
schedule: a backup task will be run every 1 day at 10 AM) as well as more complex
schedules (example of a complex daily schedule: a task will be run every 3 days, starting
from January 15. During the specified days the task will be repeated every 2 hours from
10 AM to 10 PM). Thus, complex schedules 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.
Example
Schedule parameters are set as follows