From BE 2010 R2 onwards, BE can span disk. When you span disk, it means that you can backup to a B2D folder on one disk and when it gets full, BE will automatically continue the backup on the B2D folder on another disk. You do not have to use USB disk. You can use the built-in hard disks on your media server or a mixture of USB disks and fixed hard disks.
To set up disk spanning, do the following
1) Upgrade to BE 2010 R3
This is the latest version of BE 2010. You need to be on at least BE 2010 R2 to have the disk spanning facility.
2) Define your B2D folders and enable disk spanning
Plug in your disks and define your B2D folders on them
You should use normal B2D folders for your USB disks. Do not use Removable-B2D folders as these are for things like RDX and Jaz drives.
In the B2D folder properties, enable disk spanning.
You need to set the Low Disk Space Threshold. Once the Low Disk Space Threshold is set, the device will span if it is in a device pool which we will define next. The minimum Low Disk Space Thresholdis 1 MB which you can use if you want your disk right up to the brim.
3) Define a device pool for your B2D folders.
You need to define a device pool so that your job can target this device pool. On the Devices tab, right-click on Device Pools to define a new pool.
That is it. When the first disk is full, BE will automatically continue on to the next disk. Remember that all the disk must be on-line for the disk spanning to work.
Note that disk spanning only works for .bkf files which are used by non-GRT backups. These are sequential in nature, like tapes, so they can span. GRT backups uses .img which must be allocated in their entirety so that the images can be mounted and individual items extracted. .img files cannot span disk.