I’ll be receiving 2 x 8TB USB drives soon and will be attaching them both to an Odroid C2. How can I set up DietPi to use one drive to mirror/backup the other?
Use dietpi-drive_manager to add the drives and assign perm UUID mounting.
DietPi-Sync is one option, good for daily backups, front end for rsync:
If your master drive is /mnt/usb_1, you would setup
/mnt/usb_1 = source
/mnt/usb_2 = target
Enable delete mode if you want a exact mirror of the master drive.
I would recommend not using mirror set up as it only protects you against drive failure. It does not protect you against data corruption due to hardware, software or any other catastrophic failure. Given your set up you could try the following approach.
UrBackup Server and client on the primary hard drive. With everything transferred from the SD to the hard drive except the boot loader. Then having UrBackup Server store incremental backups on the second hard drive. Restores would have to be performed off-line as operation.
In truth though it would be best to have a second device dedicated to UrBackup Server with the second hard drive. That way your backups are totally isolated from the primary server except by network connection.
Thank you gentlemen, great suggestions. Once they arrive I’ll test this out.
Hi Fourdee, I have the first 8TB drive attached and loaded up with all my movies, but when I go into DietPi-Drive Manager is sees the drive on /mnt/usb_1 but says “No filesystem / format required”. It’s already formatted to ext4. Selecting Refresh to scan for recently added drives does nothing. How can I get it to recognize the drive?
Its possible the drive has multiple partitions, with the 1st being unreadable/unknown. DietPi-Drive_Manager only checks the 1st partition and assumes you want to use the whole drive capacity.
Lets check that, please paste results:
blkid | grep sda
If it has multiple partitions, you’ll need to remove the 1st partition manually, or, do a format on the drive in dietpi-drive_manager (backup your data 1st).
If not, we’ll need to do some investigating and debug.
Got this result. Maybe the “Microsoft reserved partition” is what’s causing the problem?
/dev/sda2: LABEL="KODI Media" UUID="0dca34ad-abdc-40cc-9378-xxxxxxxxxxx" TYPE="ext4" PARTLABEL="KODI 8GB" PARTUUID="d41d2c6f-6cdf-48g2-910c-xxxxxxxxxxxx"
/dev/sda1: PARTLABEL="Microsoft reserved partition" PARTUUID="fe2323223-413b-420f-9e72-xxxxxxxxxxx"
Yep, that will be it 
Although, if this drive will be dedicated to this device, you can format in dietpi-drive_manager, it will remove both those partitions and create one in their place (which DietPi will work with).