Cloning (?) a server

[MsJamie]

I want to make a copy of my server to install at a different location; essentially, offsite backup.

 

My current server: 6x 8TB drives; 5 data + 1 parity; approx. 35 TB of data.

 

The new server: 4x 16TB drives; 3 data, 1 parity.

 

For various reasons (space, in particular), the copying has to be done on the current hardware.  What I would like to do is add the 3 16TB drives to the existing array (parity discussion below), and create a new share on them (say, /mnt/usr/backup). With a script (or rsync), I'll copy share1 to backup/share1, share2 -> backup/share2, and so on. After the backup is complete, I'll down the array, remove the 16TB drives, and rebuild parity. On the new server, I'll simply move backup/share1 to share1 after creating the share.

 

I know that I can't use 16TB drives on an array with an 8TB parity drive. Since I already have a 16TB drive that will be used for parity in the new server, I can swap that in, rebuild parity, then add the 16TB drives.  Or, I can do the copy with no parity drive.  (I'm curious which way will leave my files vulnerable for the longer period of time.)

 

Bottom line: I want a copy of all my files on 3 16TB drives, in such a way that I can simply drop them into the new server and be able to directly create an array. If I can do this via Unassigned Devices, that's fine.

 

Any ideas?

[apandey]

what you are planning will work, with a lot of reconfig / parity rebuild etc.

 

You have absolutely no spare computer where you can connect those 4 drives, boot unraid, create desired array and copy between 2 servers? that will be simplest, and you can then drop in all 4 drives including parity into new server without having to rebuild parity

 

The next simplest would be if you can connect all 4 new drives to your current server, then passthrough them into an unraid VM, then do the same process.

 

[MsJamie]

There's no room for a second computer.  I'm a trucker, and the server is at a friend's house.

[JorgeB]

Copying within the array with parity installed will be super slow, use UD and copy some data to each disk, just will need to limit each copy to the disk capacity, those disks can then be assigned to a new Unraid array and it will import the existing data.

[MsJamie]

I had to change my approach when I discovered that the newly-shucked WD drives were marked unmountable by Unraid when put into the desired enclosures.

 

Since I was going to replace the computer anyway, I pulled everything out of the house. I got the SFF PC that will be used out of storage, put all the drives into MediaSonic Probox enclosures (nice units for a little over $100), and hit the road, still pondering how I was going to do this.

 

While rolling down US-59 with the music going, I realized that I was going about this backwards.  (Especially when I realized I left the Unraid flash drive in storage.)  Since I was going to spin up a new server anyway, why not start completely clean?  So, I effectively did what JorgeB said (before I read his post). I formatted the 3 16TB drives using UD and created the array, and I am now happily copying files to it.

 

When I get to the two newly shucked drives, I suspect that UD will be able to read them directly.  If not, I do have the USB to SATA PC boards that were in the enclosure, which I *know* it can read.

 

For expediency in setting up, I am running without parity. After all, I have everything already on the other drives. What kind of speed hit could I expect if I was running with parity? My guess is that it would cut the write speed in half. Just curious.

[JorgeB]

Array to array copy with parity usually tops at around 30 to 40MB/s.

[MsJamie]

For those who stumble across this while searching, this is what I ended up doing, after much trial and error.  (Much error.)

 

1. Disabled parity.

2. Attach the 3 new data drives to the array (format, etc.)

3. Created a new share (imaginatively named "clone") and set it exclusively to the new drives.  I didn't need to lock out the new drives for the existing shares, as nothing was being written to the server during this time.

4. Open a root terminal window

5. rsync -av /mnt/user/sharename /mnt/user/clone/sharename

6. Repeat step 5 for each share.

7. Profit!

 

Yes, I'm a CLI nerd.  The advantage of using rsync from the command line is that I could interrupt it at any time with a Ctrl-C (I'm in a truck; no spinning drives while the truck is rolling, please), and re-entering the command will pick up where it left off after a few seconds.