Hello,

I backup a server with ShadowProtect SBS and I want to use two external USB disk. One for odd week and one for pair week. I use full + incremental backup job.

How can I configure ShadowProtect to handle that ?

Regards

Is the idea here to take one of the USB drives off-site each week, or will both drives stay attached to the system?

If you are planning to swap the USB drives each week, and assuing your backup schedule is one full backup per week and incremental backups each day, you would want to swap the drives just before the weekly full backup.  That way the next backup that triggers on the new USB drive will be a full backup.  Enable a retention policy on your backup job that retains as many backup sets as you want to keep.  The number you set here is the total across both drives, so if you set it to keep four backup sets, you will always have 2 sets on each disk (assuming you swap them each week as planned).

Does this answer your question?  Let me know.

Kevin

How can I continue using incrementals from the last incremental on the USB drive from two weeks ago after I just rotate the drive back in?  I want retention to stretch back a couple of months with having full backups killing my retention in a few weeks.

TIA, Scott

 Hello,

Yes the idea is to take one of the USB drives off-site each week. I've implemented your solution and I'll see if it's good tonight. If there is no full backup tonight, it will try to create one before doing incremental backup tomorrow ?

 Regards

Scott,

There are a few ways you could lengthen your overall backup chain and still rotate destination drives.  It sounds like you are looking for option 3, but you might consider any one of the following:

Option 1: Use larger disks that will hold more backup sets, so that you can increase the number of retained sets in the retention policy.

Option 2: Rotate more disks (i.e. 3 or 4), so that you can increase the retained sets in your retention policy

Option 3:  Use the 'Second and subsequent full backups are differentials' option (in the Advanced options for your backup job).  With this option, all full backups beyond the first will be created as "Differentials", which are created by comparing everything on the drive to the original full backup.  They take just as long as a full backup to create, but result in a small, incremental-sized file from which the incremental backup chain can be perpetuated.  To do this, first allow the job to create the initial full backup, then copy that backup to both drives (or all the drives) you intend to rotate.  Swap the drives just before each full backup is scheduled to trigger.  Each time it will use the original base image to create a differential, and subsequent incremental backups will be based on changes from that point on.  The retention policy will work on the differentials and incrementals created using this process, but will not touch the original full backup.  By avoiding full backups (other than the initial full), you save considerable disk space and can have a much longer backup chain.

NOTE about option 3:  The size of each differential can increase over time as the system is used, or if major changes to the disk are made, such as if the drive is defragmented.  They still won't be near as big as a full backup, but it can negate a little of the space-saving benefit of this process.  If this becomes a problem, you can always wipe the destination drives and start over with a new full backup to correct the problem.

Kevin

Great idea, but this spawns new questins.  How do I rotate three drives?  Do I creat three different backup plans, and how do I schedule each plan? One week on, two weeks off?

You should be able to do this with one backup job and schedule.  To rotate three drives, you might use a weekly backup schedule with a full once per week, and swap the drive with another each week, just before the full backup.  It works exactly the same as with two drives, except that you now have more space, so you can keep a longer backup chain.  Therefore, you can set your retention policy to keep more backup sets (with 3 drives, you might as well pick something divisible by three, like 6).  If you are using Option 3 (above), you would need to copy the initial full backup to all three drives.

Kevin