Backing the Same Data up Multiple Times

[JonathanB]

Okay. This is what I'm looking to do:

I've got 2 seperate B2D devices (Actually one is removable, the other is not).

On the removable one I planned to backup everything except for 1 of the DFS replicated folders. I will run a full backup on Friday nights and incremental on Monday - Thursdays. I planned on swapping these disks on Fridays to take offsite.

For the non-removable disk, I planned on backing up the 2 DFS replicated folders. I plan to do a full backup on Sunday and Thursday nights. Then I plan to do differental backups every 30 minutes during business hours. (This shouldn't effect performance too much because users aren't directly accessing this server)

I plan on using modified time for both of these backups (Because I've got DFS repliciated folders).


Will these two backup plans cause problems with each other? --- Will I possibly miss files in my incremental backups because both backups include a common DFS replicated folder?

I'm currently using Backup Exec 12.

Thanks.

Jonathan

[CraigV]

If you time-stamp them, then the non-removable backup job would be backing up your information since your last backup 30 minutes prior. FOr the removable job, those changes would be seen and the job should be backing up those files, as they've changed since the night before's job ran.
I don't see an issue doing it this way, although keep the backup times apart, and don't run the jobs together.
If the time is modified by the 2nd job every 30 minutes, this will carry through to that night's backups.
The easiest way is to test this with something else, document it, and then put it into production.

[JonathanB]

This is what I did:

Created 2 seperate Folders on a single DFS share.
Folder1 - Test1 contains 1.txt - 10.txt
Folder2 - Test2 contains a.txt - j.txt

Each file contains its file name without the extension as its data.

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Created 2 seperate Selection Lists. Both include Test1. First selection list contains Test1 and Test2. Second selection list contains Test1 and a second folder of unchanging data.


The first selection list will be for the differental backups. The second selection list will be for incremental

I created two different media sets to use with these, but used the same B2D device.

I used modified time to back these up.
---------------------------------------------------------------------------------------

Full Backup - Diff ( Backed up all files)
Full Backup - Incremental ( Backed up all files)

Changed files ( Changed 1.txt, Changed 2.txt, Changed 3.txt)

Differental Backup (Backed up 1,2, and 3)
Incremental Backup (Backed up 1,2, and 3)
----------------------------------------------------------------------------------------

Changed Files (Changed 4.txt, Changed 5.txt)

Differental Backup (Backed up 1 - 5)

Changed Files (Changed 6.txt , Changed a.txt , Changed b.txt , Changed C.txt , changed d.txt)

Differental Backup (Backed up 1 - 6, a - d)
Incremental Backup (Backed up 4 -6)
----------------------------------------------------------------------------------------

Change files (Changed 7.txt , changed e.txt)

Differental Full Backup (Backed up all files)
Incremental Backup (Backed up 7)
----------------------------------------------------------------------------------------

Change files (Changed 8.txt , changed f.txt)

Incremental Full Backup (Backed up all files)
Differental Backup (Backed up 8 and F)
--------------------------------------------------------------------------------------



So in summary it looks like Backup Exec keeps the two backups seperate. I'm not sure if it seperates by Media type or by Selection list, but the two do not look to effect each other.

Jonathan