I know that Windows 2008 R2 and 2012 were limited to 2TB volumes (or at least the size of files) due to the fact that internally Windows Server Backup uses VHD files which are limited to ~2TB.
I can't find anything in the docs from MS regarding 2012 R2 and whether internally WSB uses VHDX instead, bumping the limit up to 64TB. We're looking to backup a few volumes with ~4TB per volume. I'd hate to have to go and reallocate them just to get backups working.
MS has to know that people have backup needs for volumes larger than 2TB, right?