User`s guide

o Monthly: 5 years

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:

o Daily: 1 week

o Weekly: 1 month

o 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.

6.2.9.5. 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. 178), weekly (p. 180), or monthly (p. 182) 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.