Problem creating Grandfather, Father, Son backups

[m.e.]

Hello Admin,

thanks for your answer. Could you please explain more precisely:

For example, is it corret that in order to restore an image, these days' backups are required (after ">")

Day 1: Full Image > 1
Day 2: Incremental > 1,2
Day 3: Incremental > 1,2,3
Day 4: Differential > 1,4
Day 5: Incremental > 1,4,5
Day 6: Differential > 1,6
Day 7: Incremental > 1,6,7
Day 8: Incremental > 1,6,7,8

Does this mean that AS SOON AS A DIFFERENTIAL IMAGE has been created, the user may delete ALL OLDER incremental images. Future incrementals do not need those old incrementals because they will use the latest backup (the differential), and the remaining old differential images only need the initial Full Backup.

Is this correct? Are the numbers behind ">" (required backup files) correct?

This also means that instead of

Full_V1_1.DBI
Incremental_V2_1.DBI
Incremental_V3_1.DBI
Differential_V4_1.DBI
Incremental_V5_1.DBI
Differential_V6_1.DBI
Incremental_V7_1.DBI
Incremental_V8_1.DBI

One could also name the backup files like this to indicate their dependencies: The first 3-digit-block indicates "Full," the second "Diff", and the third "Inc":

Full_v001-000-000_1.DBI
Incremental_v001-000-001_1.DBI
Incremental_v001-000-002_1.DBI
Differential_v001-001-000.DBI
Incremental_v001-001-001_1.DBI
Differential_v001-002-000_1.DBI
Incremental_v001-002-001_1.DBI
Incremental_v001-002-002_1.DBI
Full_v002-000-000_1.DBI
...

[admin]

Hello Admin,

thanks for your answer. Could you please explain more precisely:

For example, is it corret that in order to restore an image, these days' backups are required (after ">")

Day 1: Full Image > 1
Day 2: Incremental > 1,2
Day 3: Incremental > 1,2,3
Day 4: Differential > 1,4
Day 5: Incremental > 1,4,5
Day 6: Differential > 1,6
Day 7: Incremental > 1,6,7
Day 8: Incremental > 1,6,7,8

Does this mean that AS SOON AS A DIFFERENTIAL IMAGE has been created, the user may delete ALL OLDER incremental images. Future incrementals do not need those old incrementals because they will use the latest backup (the differential), and the remaining old differential images only need the initial Full Backup.

Is this correct? Are the numbers behind ">" (required backup files) correct?

This also means that instead of

Full_V1_1.DBI
Incremental_V2_1.DBI
Incremental_V3_1.DBI
Differential_V4_1.DBI
Incremental_V5_1.DBI
Differential_V6_1.DBI
Incremental_V7_1.DBI
Incremental_V8_1.DBI

One could also name the backup files like this to indicate their dependencies: The first 3-digit-block indicates "Full," the second "Diff", and the third "Inc":

Full_v001-000-000_1.DBI
Incremental_v001-000-001_1.DBI
Incremental_v001-000-002_1.DBI
Differential_v001-001-000.DBI
Incremental_v001-001-001_1.DBI
Differential_v001-002-000_1.DBI
Incremental_v001-002-001_1.DBI
Incremental_v001-002-002_1.DBI
Full_v002-000-000_1.DBI
...

The dependencies you describe for the backup versions are correct and yes users can delete old incremental backups after creating a new differential backup.

[m.e.]

Thank you!!!

[Froggie]

But please remember... once you remove those earlier Incremental backups, you cannot return to those time points via restoration.  You can only return to the time points that remain, assuming they all have "parent" images to be referenced from.

[Froggie]

I would also suggest that Hasleo implement image deletion through their User Interface.  That way the user will know, since Hasleo does, what images (and their children) will be affected by an image deletion.  Not only will they know, but if the user goes ahead with the deletion, HBS will also eliminate the "children" of that image that no longer have a previous reference and have become orphaned.

This makes the user process very simple when it comes to cleanup and image management.

[RobLatour]

@Froggie @Admin

Thank you very much for looking into this.  I've just installed the latest version (dated today).

As luck would have it, next month (January 2024) the first Sunday of the month appears in the second week (on the 7th) - so it'll only be a few weeks from now and we should see it run correctly!  I'll keep you posted.

Best Regards,

Rob

[Froggie]

Rob, just tested it... works fine.

[m.e.]

Hello, I wanted to present a backup system that I might be interesting. It uses one backup drive, not several.

Hour -- Type

01 Full
02 Inc-A
03 Inc-A
04 Inc-A
05 Inc-A
06 Inc-A
07 Inc-A
08 Inc-A
09 Inc-A
10 Inc-A
11 Inc-A
12 Inc-B ###
13 Inc-A
...
23 Inc-A
24 Inc-B ###
25 Inc-A
...
35 Inc-A
36 Inc-B ###
37 Inc-A
...
47 Inc-A
48 Inc-B and Diff-B ###
49 Inc-A
...
59 Inc-A
60 Inc-B ###

Inc-B will contain the difference to the last Inc-B (or Full). On hour 48, both a Diff and and Inc-B are created.

Advantages:
Differential images get larger and larger as time passes, forcing the user to create a new Full Image
Frequent incremental Images with no Differential images inbetween are high risk if an incremental depends on hundreds of previous incrementals
By creating "Inc-B" incrementals, we create a "mix" of the advantages of Differential and Incremtal backup:
Inc-B incrementals do not require any Inc-A incrementals, and not Differential images. Differential images are created less frequently, for additional safety.
As soon as the user uses Inc-B images, all Differential Backups will ALWAYS create an additional Inc-B backup AT THE SAME TIME. The user can therefore later choose to delete EITHER the Inc-B OR the Differential, because subsequent images will work irrespectively (because Inc-B and Diff are the exact same state). To indicate that this system is in use, Differentials are called "Diff-B".
The system also makes backups faster because fewer Differential Backups will be made and/or because the creation of an incremental at hour 1000 will not have to check 1000 previous incrementals, but only a fraction (the Inc-Bs).

For example Backup on day 43 requires:
Days 1, 12, 24, 36, 37, 38, 39, 40, 41, 42, 43
Instead of 1,2,3, .... 42, 43

Of course a similar system could also be created by automatically merging 6 old Incrementals into 1 and verifying the contents.

[Froggie]

Your process requires (2) independent image chains and cannot reference INCs in other image chains. Software would require a re-design.

[m.e.]

(Small number theory mistake, I should have started with "Full-00", OR assigned Diff 49 (and Inc-B 07) (instead of full 01, OR Diff 48/IncB-06))

Yes, perhaps my point was more to demonstate the problem with a high number of incrementals and increasing size of differentials, forcing the user to make a new Full Backup often.

Let's see if it is possible to get HBS to do this to some degree:


00 Full
01 Inc-A
...
11 Inc-A
12 Inc-B ### user removes 02,...,11 before creation of 12
13 Inc-A
...
23 Inc-A
24 Inc-B ### user removes 13 ... 23 before creation of 24
25 Inc-A
...
35 Inc-A
36 Inc-B ### user removes 25 ... 35 before creation of 36
37 Inc-A
...
47 Inc-A
48 Inc-B and Diff-B ### user removes 37 ... 47 before creation of 48-Inc-B. User then created 48-Diff-B and MOVES Diff-B into separate folder. Inc-A-49 (and Inc-B-60) will now be based on Inc-B 48 (it is not so imporant to make it also work with Diff, this possibility is unnessary and not available in this solution)
49 Inc-A
...
59 Inc-A
60 Inc-B ### user removes 49 ... 59 before creation of 60.

Does this work?