How to continue incremental backups after replacement drive installed

[DaveD]

Retrospect 17.5.2.103, Windows 10 desktop. I replaced my out-of-space C SSD drive yesterday with a new one and used Samsung's cloning software to duplicate the old drive to the new. That appeared to work flawlessly, but when Retrospect did its nightly incremental backup, it went to the E drive where the old SSD now resides instead of the new C and, thankfully, backed up nothing. I can redefine the backup script to go to the new C drive, but I'm concerned that it will do a full backup first time through, and I would rather that didn't happen--I would like to continue doing incremental BUs, since the new drive appears to be identical to the old except for drive ID, or whatever it is that causes Retrospect to follow the physical drive regardless of the drive letter it currently has.

What will happen when I redefine the source drive on the script? And if it will by default do a full backup, any way I can change that? Or must I settle for a full BU?

[Lennart_T]

I'm pretty sure that Retrospect will not perform a full backup just because the files are on another drive. That is because it's the same computer with the same Windows version.

[DaveD]

Unless I get a more definitive answer I will have to try a manual version of the nightly backup. This backup, to a local USB drive, doesn't matter so much space-wise, as the 4TB backup disk has enough open space to hold the 500GB or so that a full backup will take. But Retrospect does an incremental backup of only my data to cloud storage, approximately 180GB, every Thursday night. That incremental backup normally consists weekly of 3-4GB, but if it backs up all the data would take many hours and exceed my allocated bandwidth. So I must be sure!

Any additional thoughts?

[Nigel Smith]

On 7/27/2022 at 4:28 PM, DaveD said:

Any additional thoughts?

Make a new script in Advanced mode with the same options, source(s), destination, and selectors as the script you are worried about and then "Preview" to see what's going to happen.

[DaveD]

Nigel, the only "Advanced mode" I find is in the Backup Wizard; I use that mode, and the only option there is a check mark icon at the top of the screen that has Retrospect inform me about whether the script appears valid or not. While there, I can also check media. This gives me no indication as to which or how many files will be selected. Am I missing something?

Note that I simply redefined the source volume as "C:", checked my selectors, and ran it manually. It did indeed work as we thought it should, doing an incremental backup in the same manner that it did in the old drive. So yes, it works as it should once the source volume is redefined. 

[Nigel Smith]

21 hours ago, DaveD said:

Am I missing something?

It's probably me -- I'm a Mac rather than Windows user.

But pp12 of the Windows RS v17 manual shows a "Preview" button, so I think the functionality is there if you dig around a bit.

[DaveD]

As (hopefully) a final entry in this thread, a couple things:

Nigel mentioned making a new script and a "Preview" option. Yes, I found that this does exist when making a new script, but not on an existing script. I chose not to make a new script on the cloud backup because the script and backup set definitions are complex. In any case, it worked somewhat properly, but not totally. Where Retrospect weekly backs up 2-3GB to the cloud, the backup I finally did yesterday backed up 50-something GB out of total backup selection size of ~180 GB. I don't know why it didn't backup either the whole 180GB or, as normal, 2-3GB, but I will settle for that.

As for the local backup, after redefining the backup source disk as the real system disk (C:), it did indeed backup only changed data as it usually does. 

I also found that the local backup from the wrong disk (the old C drive, now the E:) can be "forgotten" and Retrospect will groom it out of the backup set. That is a nice feature and a good way to recover from an "oops"! ...Or, I believe it is  a nice feature. Retrospect is as I write grooming an "oops" from last night, the first incremental to my USB drive after swapping the offsite and onsite disks, which I do every few weeks. Again, I forgot to redefine the backup source when I brought the second drive in. But  grooming the bad backup from last night is taking a while so I don't know how successful it's going to be.