Transferring Files Within the Unraid Server
If you are using Windows Explorer to move files between drives, you are actually copying the files TWICE across the network, from the Unraid server to your Windows machine, and back again. For copying a few files, this is not a problem. But if you are moving a lot of data, here are faster methods.
Midnight Commander - Easy to Use GUI Tool
Use Midnight Commander and PuTTY instead. Type mc at the command prompt in a telnet/PuTTy session to start the GUI. Midnight Commander is built into Unraid v4.3 and up. For earlier versions, and a link to PuTTY (an alternative to Telnet that allows use of a mouse within mc), see this thread). Midnight Commander is a Linux console tool, and needs to be run from either the physical console on your Unraid server, or from a Telnet console on your desktop station. For more information, see the Telnet page, which includes information on PuTTY.
Move Files Overnight
If you go to the Unraid server and run Midnight Commander from there, you can use it to move a bunch of files overnight. But if you use mc from a Telnet prompt from your Windows (or other) workstation, you will have to leave the computer on and the Telnet session open until the disk operations are complete. If the Telnet session ends, so does the copy or move operation.
But with a little knowledge of Unix commands, you can easily start moving files around your Unraid server and then shut down Telnet and your workstation. The key is the "nohup" command (nohup means "no [don't] hang up"). If you put "nohup" before any command and an ampersand (&) afterwards, the command will run in the background until it is complete. Your command prompt will return immediately.
So, for example, if you wanted to move a bunch of movies from Disk1 to Disk2, you could use this command from a Telnet (PuTTY or otherwise) prompt ...
nohup mv /mnt/disk1/Movies/* /mnt/disk2/Movies &
Do a quick check to see that files are starting to appear in the destination folder to make sure you didn't have a typo in the command, and then exit from the Telnet session. The files will continue to be moved as fast as Unraid can move them, and use ZERO network bandwidth. Make sure it is complete before shutting down your Unraid server, as copying hundreds of gigs can take a long time to complete even at the fastest speed.
nohup can also be used with the "cp" (copy) command (see Unix Commands section below)
nohup creates a log file called 'nohup.out' with the command output. The basic "mv" command doesn't create any output, but "cp" outputs the name of each file it copies. If you use "cp" to copy a LOT of small files (300,000+), you risk having nohup.out get quite large - large enough to fill up your Unraid server ramdisk - not a good thing.
Unix Commands
There are two effective methods available to move files from one drive to another from within Unraid (v4.x and later).
Copying files
1) Copy the files from disk# (where '#' is the number of the disk in Unraid)
cp -r /mnt/disk# /mnt/disk#
Example:
cp -r /mnt/disk4 /mnt/disk8
Copies all contents of disk4 to disk8. All files/directories on disk4 remain.
Note the above example will create a dir named 'disk4' on disk8 with the contents underneath it. The original file date/time stamps will not be preserved.
See below for syntax to copy the root directory names only with all files underneath them and preserve the original file date/time stamps.
The -r option causes the cp command to copy directories recursively. It is not necessary with a simple file copy.
If you want to follow along as the copy proceeds, add the -v option (requesting verbose output).
To copy the root directory names only and everything under them, preserve the original file date/time stamps and log the output to a text file on the flash drive in a format readable by an editor like windows notepad use this syntax:
cp -r -v -p /mnt/disk4/* /mnt/disk8 | todos > /boot/disk1copy.txt
Moving files
2) Move the contents of disk1 to disk2 using the mv command
mv /mnt/disk#/ /mnt/disk#
Example:
mv /mnt/disk1 /mnt/disk4
Moves all contents from disk1 to disk4. All files/directories on disk1 are now gone.
Caution: Using the move command may be potentially dangerous as it will copy to the destination drive and then delete your data file(s) from the source drive. In the interest of maximum safety, you may want to use copy instead.
Quotes
If you want to copy or move entire folders from one drive to another, and the folder names have spaces in them, you need to use "quotes" around the folder name, as in this example:
mv /mnt/disk2/"The Empire Strikes Back" /mnt/disk3
In the above example, the entire folder called The Empire Strikes Back would be moved from Disk 2 to Disk 3 with the same sub-folder structure.
Wildcards
Wildcards are available as well. For example, if you want to copy all of the files from Disk 2 over to Disk 3, use the mv command like this:
mv /mnt/disk2/* /mnt/disk3
In this example, all files and folders on Disk 2 would be relocated over to Disk 3 in the exact same folder structure as it was on Disk 2.