I am considering building an unRAID 6 server to replace a drobo.  I have a question about backups.  Is it possible to use Crashplan to backup the unRAID array to an external USB 3.0 NRAID enclosure connected to the unRAID server. I have about 6TB of data to backup.  My thought was to backup to the external enclosure periodically then move the enclosure to an offsite location. The exclosure will be populated with 4 high capacity hard drives that are spanned to create one large logical drive. Particularly critical files would be backed-up online.  Is this feasible? Achieving USB 3.0 transfer rates would be critical to seed the original backup. 

I am considering building an unRAID 6 server to replace a drobo.  I have a question about backups.  Is it possible to use Crashplan to backup the unRAID array to an external USB 3.0 NRAID enclosure connected to the unRAID server. I have about 6TB of data to backup.  My thought was to backup to the external enclosure periodically then move the enclosure to an offsite location. The exclosure will be populated with 4 high capacity hard drives that are spanned to create one large logical drive. Particularly critical files would be backed-up online.  Is this feasible? Achieving USB 3.0 transfer rates would be critical to seed the original backup.

I think the first thing is to check if CrashPlan can see your USB disk. It would be mounted outside the array and probably using a Plugin called Unassigned Devices. I did try with a small disk a got but it was not visible to CrashPlan however that was just a quick test.

 

Even if you can get this to work, every time you plug in the USB disk to your unRaid system CrashPlan would need to do a full scan of the files to find out what has been done and what to do. Might take some time with that much data.

 

Have you considered other options, like building a small backup server and doing an Rsync backup over the network? Could be a rather small box with three or four drives and a mini-ITX board.

 

Edit:

Was actually able to add a mount point in CrashPlan to an attached USB drive so it still might be an option. I used an USB 2 disk so I don’t know how unRaid will handle USB 3 disks. What files system to use must also be considered as well as that the backup is probably in a CrashPlan format so you would need that to do a restore.