Understanding UrBackup

I got the Odroid N2+ and get UrBackup running. Everything works rather well, but I have some questions. Sure they are not special dietpi questions, but maby it’s ok to ask them here.

  1. If I connect one or several external SSDs and want to write to all them, how can I do it? Because I can just set one path to save the backup. Can I make something like software RAID0 or something else?

  2. If I turn the PC (client) on, then the backup process starts. But if I turn it off, while backup is still running, the backup process doesn’t start later at the point the process was interrupted. It’s a big problem, because if I make a full backup, I need to run the PC for the whole night and longer (about 1TB). If I interrupt it, the whole time is just lost.

  3. What exactly is image backup? Can I do full image backup of Windows, to install it on another systems?? So is it something like mirrowing the whole system SSD?


  1. I think right now it supports only one backup path (per client). But you could just sym link all your directories to one path and back this up.

  2. I think for first backup there is no way around to let it finish in one run.
    In future backups it will then only copy new and modified files, if you use incremental file backup.

  3. Yes exactly, you can create full images of a system and flash it to a hard drive, but it comes with some limitations:

Image backups only work with NTFS formatted volumes and with the Windows client or with extX and XFS and the Linux client. The drives must be MBR or GPT partitioned, the partition must be a primary one. Dynamic volumes are not supported. Mirrored dynamic volumes work, but are not officially supported.


1 Like

What do you mean by

[quote=“Jappe, post:2, topic:16584”]
But you could just sym link all your directories to one path and back this up.
[/quote] ?

But if I want to have 2 or more full backups (in case one of them is corrupted), so each time I must wait till it fully done, isn’t it?

So does it make an iso or img file of the system drive?

e.g. I want to backup /mnt/hdd1 and /mnt/hdd2 I can create a symlink for both to another location like /mnt/backup/. Inside this directory would then be hdd1 and hdd2
This can be done with the ln command and the flag -s.

If you want full backups, then yes. But if it gets corrupted you could just create a new backup from source and also enjoy the advantages of incremental backups.

I think you can create an image of any drive meetings the requirements, it does not have to be a system drive. Per default its and vhd image. I did not find any informations in the their docs to save it as another format.

oh, ok… so is it something like software RAID0?

The thing is, if the source is also corrupted and I have just one full backup from this corrupted source, that would be the worst case. So I think, it’s a good idea to have two or three full backups maybe one per month.

By the way, one more question. Is there a possibility to automatically delete one full backup? Lets say, I want two full backups and want always delete the older one.

and vhd image I can also flash like iso or img? With etsy, rufus or smth like this?

No, with RAID you have multiple disk shown as one. here you just link some paths to one path. Onewindows systems this is called a shortcut, I think.

Yes, Rufus can handle it. I’m not sure about Etcher.
But you can also directly mount the image, no need to flash it (if its just files and not a whole OS)

Regarding #1: Do you want to use something like a logical volume manager?
In a couple of days I want to generate a post about lvm2 in out DietPi Blog.

In short words: apt install lvm2.
Format disks (via mkfs.ext4).
Then use the commands pvcreate, vgcreate, lvcreate, pvdisplay, pvs, vgdisplay, vgs, lvdisplay, lvs.

Or have a look to the already existing blog post on how-to use mdadm Using a RAID system with DietPi – part 1 – DietPi Blog

ah, ok. Need to test it. I think dietpi can not manage it in drive_manager, isn’t it?

Oh, I think, this could be a good idea. The thing is, can I hotplug the SSDs after matching them together as LVM?

that’s maybe the best solution, isn’t it? Just making RAID0 of 4 SSDs and that’s it.

Will try it the coming week. Surely I will have some questions again :smiley:

However, using Raid 0 does not provide fault tolerance or redundancy, the failure of one drive will cause the entire array to fail. In the case of 4 Raid member, another raid level might be more appropriate. Standard RAID levels - Wikipedia

What exactly you like to do? Temporary remove raid members to connect them to other systems or just in case of drive failure?

just want to backup the data on more than one SSD via UrBackup and N2+

The question is whether these drives should be connected all the time or whether you plan to remove them from time to time. Also, both lvm and mdadm are software raids and the drives will only work as long as they are connected to the system/SBC. They will not work if you remove drive and connect it to another system/SBC.

ah, ok, I want to hotplug the drives from time to time. So what can I do in that case?

ok just to my understanding, what is the reason to hotplug the drive? And why do you need to create your backup on 2 drives? We would need to know a little bit more on your use case to recommend something.

  1. Sometimes I want to take the SSDs with me, for some mobile work. But maybe I should just make some other strategy for that.
  2. I have one T7 with 2TB and it’s not enough. Because N2+ has more USB ports, just thought, it would be a good idea just to plug in more SSDs. Just have no money to buy 8TB SSD or something like that. So want to buy the TBs step by step. But maybe it’s a better way, just to buy 8TB with SATA-USB-Adapter. But the thing is, even 8TB will be not enough in the future.

My proposal: Use lvm and keep the disks fix at the N2+ for your Urbackup.

Use a different disk for your mobile usage (and synchronize them to the lvm), or take the whole N2+ with the lvm disks on your trips.

Forget to use disks in a RAID/lvm and temporarily use them in a different environment.

1 Like

mmmhh, thanks, I think this will be the best solution :slight_smile:
So i will try to setup the lvm with one or two more 2TB SSDs.

@dieterpi: Blog post is ready, you can read it there: Merging disks to a large logical volume in DietPi – DietPi Blog.