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I have a question about a Grandfather, Father, Son 21 Backup Strategy... (the 21 stands for the number of volumes) which I have worked out on the following spreadsheet (see in Google Drive): https://drive.google.com/open?id=0B4UUQH5An0uuYkhiSF9aX25ZUzQ

As far as I can tell, it totals to:

4   Father Volumes
4   Son Volumes
11  Grandfather Volumes
1   Yearly Volume
20  Volumes Total (Normal Year)
21  Volumes Total (Leap Year which causes Week 53)

Will 12/30/2017 be the volume I should backup for the yearly backup? It seems strange to me that it occurs on a Thursday.

leeand00
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1 Answers1

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It would be nice if we had a week, a month and a year that all had a common denominator in days. But we don't. Therefore, there's no correct mathematical answer to your question.

It's just a scheme. Pick any day for your yearly backup. It could be within your "grandfather" or "father" cycles, last day of the year, last saturday of the year. What difference would it make anyway?

The safest practice could be e.g. taking a yearly backup on the last night before the last working day before thanksgiving and store it offsite at your grandmother's house in different state. I'll just give that as my ultimate solution.

Esa Jokinen
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