# Understanding Image Backups (Incremental)

I think Urbackup is fantastic & been using for # of years - mostly for Windows/file backups, but since Windows 10 doesn’t support the Win7 image backup to a network location, have decided to employ Urbackup for images as well.

So, I understand there’s the restore CD/usb stick - which I haven’t tried. I use the uncompressed option in settings so I get .vhd files, which can be mounted.
But, what exactly would I get mounting an incremental image? When I open it with 7-zip, it looks like a complete image of the drive, but since the actual archive is tiny, it can’t be ‘real’ - right?

Part of the reason I’m asking this - the Urbackup drive is not RAID, so as add’l protection against failure of the Urbackup drive, I use scripts to make a copy of the latest (file) backups to an external drive weekly. I think even if the last backup was incremental, copying ‘current’ gives me everything.
But, what about making copy of the image BU?
Since there is no equiv of ‘current’, and the file name of the image backup is unknown, I started writing a script to find the newest folder that had ‘image’ in it. But, I’m thinking this isn’t going to work/ I don’t know whether this is a full or incremental image

Maybe I should disable incremental backups and do only full? Still would like to know how one would deal with mounting an incremental image .vhd without using Urbackup’s restore program…

If you don’t have a GPT formatted disk, assemble_disk_image.bat might work to convert a incremental vhd to a full vhd (assemble_disk_image.bat C:\path\to\src.vhd D:\disk-output.vhd). Otherwise you have to copy the whole incremental chain (all image backups since the last full if you run “incremental-to-last” or the last full + the “differential” image (incremental to last full).
Something like https://docs.microsoft.com/en-us/powershell/module/hyper-v/convert-vhd?view=win10-ps (or the VBox equivalent) creates full disk images as well, I guess.

Thank you Uroni! I think I understand better - the incremental image is a differencing VHD with parent(s). 7-zip is able to open the incremental image as a complete image as long as all the image backups are in-place on the Urbackup drive.

If I copy the full image to external drive, that image can be used/opened.
I got some idea of using Powershell to change the location of the parent if the images are copied to new location, but no success yet (exception about the parent having been modified) -
Until/if I figure it out, I think will just try to copy the last full image to external location monthly - was doing a VB script for wscript.exe, but if I keep incremental images, I think have to learn/use powershell to do a script that can identify child vs parent vhd’s…

Hello RG888,

I run two copies of UrBackup Server.
Each on its own machine.
Each client backs up to both machines.
If one machine goes down, I still have another pristine server with all backups intact.
Clients still continue the full backup regime to the surviving machine.
Repair the broken machine, then backups will resume to both machines with little intervention.
No scripts, no confusion…