We have a Windows Server Backup schedule that backs up our 'main' Windows 2008 server, which does our AD, Exchange, Domain controller, file hosting and a bunch of other stuff.
Now we want to offload this backup to an online location, because we don't want to have to keep taking the backup disk home with us, and it will allow for more frequent offsite backups.
The whole thing is just too big (350G) to finish a complete transfer before the next backup cycle starts, so I need it to transfer incrementally, like rsync does.
The problem I see is that Windows Server Backup makes a new folder each time it is run, with the date in the folder name. The files that it puts in that folder look like they're about the same each backup (same names), but rsync doesn't seem to think so. It transfers the files fully each time, even if I use --compare-dest to point it to the previous files. Rsync is supposed to know about modifications to large files and transfer only those differences, as it compares blocks in a file with the already existing target file of the previous transfer. But apparently Windows Server Backup thwarts this cleverness somehow.
Has anyone ever tried to accomplish this, and had any success with it?