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#Hanoi towers pattern full
#Hanoi towers pattern series

the pattern starts with a full backup since the very first backup cannot be incremental.

differential backups on all intermediate levels (B, C and D for five-level pattern).

full backups on the last level (E for five-level pattern) – the rarest backups in the scheme, take more time and occupy more space in storage.

incremental backups on first level (A) – to gain time and storage savings for the most frequent backup operations but data recovery from such backups takes longer because it generally requires access to three backups.

You can set up the backup scheme while creating a backup plan.Īcronis implementation for the scheme has the following features: But Acronis Backup & Recovery 10 provides you with automation of the scheme usage. The Tower of Hanoi backup scheme is generally too complex to mentally calculate the next media to be used. So every additional backup level doubles the maximal roll-back period for your data. For the five-level scheme you can also recover data backed up two weeks ago. Having four backups, you can recover data as of today, yesterday, half a week ago, or a week ago.

So the scheme allows for efficient data storage: more backups accumulate toward the present time. All the outdated backups have to be deleted. The Tower of Hanoi backup scheme implies keeping only one backup per level. The table shows the pattern for the five-level backup scheme. So, the five-level Tower of Hanoi backup scheme cycles the pattern that consists of 16 sessions (moves from 1 to 16 in the above figure). Commonly an N-level scheme pattern contains (N-th power of two) sessions. It operates with Sessions instead of Moves and with Backup levels instead of Rings. The Tower of Hanoi backup scheme is based on the same patterns.

The solution is to shift the first ring every other move (moves 1, 3, 5, 7, 9, 11…), the second ring at intervals of four moves (moves 2, 6, 10…), the third ring at intervals of eight moves (moves 4, 12…), and so on.įor example, if there are five rings labeled A, B, C, D, and E in the puzzle, the solution gives the following order of moves: You are only allowed to move one ring at a time, and are prohibited from placing a larger ring above a smaller ring.

#Hanoi towers pattern series

The goal is to move the ring series to the third peg. In the puzzle a series of rings are stacked in size order, the largest on the bottom, on one of three pegs. The Tower of Hanoi scheme is based on a mathematical puzzle of the same name. The Tower of Hanoi (ToH) backup scheme is a useful compromise. The need to have frequent backups always conflicts with the cost of keeping such backups for a long time.