[HowTo] Retrosmc - Retrogaming on OSMC with EXT USB Drive

If you’re like me, you have a lacking space SDCard in your RPi running OSMC as all you ever do is stream content, but now you want to play some ROMs. If you try to install full RetroPie, you will run out of space and OSMC will panic and die with no space left.

So I decided to do a few quick & easy edits, to make it install to a USB Drive, plugged in to a connected powered USB hub.

(I thought this was going to be a lot harder to figure out, but was pretty straight forward after looking through all the source files. Would be nice if they just added an install location option in the menu system, maybe they will someday.)

Plug in your USB Drive to the RPi, Format it EXT4.

Note: If emulationstation for you is not starting, try to run it through ssh and you will see errors. (Example: emulationstation “Line 12” permission denied.) You probably didn’t format your USB Drive EXT4 and it is probably FAT32 which you cannot launch programs from, as you can’t properly use execute, without some workarounds.

Make sure the SSH Server is running in OSMC, Find it under services in the OSMC Settings (Not in KODI’s main settings).

SSH into your OSMC installation.

ssh osmc@ [Your OSMC IP]

Note: You will lose all your data on your USB Drive if you continue with this!!!

Find your USB Drive with:


MMCBLK0 is normally your SDCard (Do not kill this one).

My USB Drive was SDA (8GB).

umount /dev/sda
fdisk /dev/sda

Delete all partitions with:


Press partition numbers until all removed.


Write partition table.


Then quit


Format our usb drive with EXT4 (Linux File System).

mkfs.ext4 /dev/sda -L RETROPIE

Rename our drive label RETROPIE (If you forget to label your drive in the last step properly.)

e2label /dev/sda RETROPIE

Remove the USB Drive from the port and reinsert it. It should now be remounted under /media/RETROPIE/

Download the installation script to your OSMC home directory:

cd /home/osmc
wget https://raw.githubusercontent.com/mcobit/retrosmc/master/install-retrosmc.sh

Make it executable:

chmod +x install-retrosmc.sh

Then run it:


Click Install retrosmc

After it is finished downloading the setup scripts (ie you see the [Choose an option] menu) CLICK CANCEL!!! until you are back to the CLI (Command Line). Don’t worry it downloaded all the files we need to modify, from clicking the first menu option. We will come back here after a few more preliminary steps.

Edit this file below to change the install location to our USB Drive that we formatted above.

cd /home/osmc/RetroPie-Setup
nano retropie_packages.sh

Find this:

#main retropie install location

Modify this line to:


Press ctrl x
Press y
Press [Enter]

Note: You will need a few 100MB’s free on your SDCard for all the extra Linux Arm packages it requires to do what it does, but all the frontend (emulationstation), emulators and ROMs will go to the USB Drive, cross your fingers you have enough space for the packages and continue! :smiley:

This will show you, your free space on the SDCard while logged in via SSH look at the largest capacity Use% column:

df -h


Click Install retrosmc again.

Once you get to the second menu of the Retrosmc [Choose an option], select “Binary-based installation (recommended)” and press enter.

After the RetroPie-Setup script is finished the installation, press Enter for all windows, mentioning DATA and BIOS files for the emulators. When back at the main RetroPie menu, choose “Cancel”!

Install the Retrosmc Launcher Add-on, you will find your shortcut under Program Add-ons in KODI after a restart.

You can exit the menu by choosing Cancel at the bottom after every task.

nano /home/osmc/RetroPie/scripts/retropie.sh





Press ctrl x
Press y
Press [Enter]

Let’s move the roms folder to the Flash Drive as well now and make a soft system link to it.

Rename the current roms folder so it won’t stop our soft system link from linking.

cd /home/osmc/RetroPie
mv roms roms2

Make the directory RetroPie on your USB Drive, Note linux file system is case sensitive so you can have a two folders named RetroPie and retropie.

mkdir /media/RETROPIE/RetroPie

Make a new roms directory on the USB Drive or network share.

mkdir /media/RETROPIE/RetroPie/roms

Install rsync to copy the old roms folder to the USB Drive because it has all the folder structures you need for Retrosmc.

sudo apt-get install rsync

Copy the old roms2 folder to the new roms flash drive folder.

rsync /home/osmc/RetroPie/roms2 /media/RETROPIE/roms

Soft system link our USB Drive folder back to its prior location.

ln -s /media/RETROPIE/RetroPie/roms /home/osmc/RetroPie/roms

Copy your ROMs via an SFTP client depending on your OS, I just use rsync/scp or WinSCP is good for windows if you still use that.

Note: I’m not sure how all this will effect if you try to update the RetroPie scripts so proceed with caution you might have to do all this again.

Move the setup files to the USB drive.

mv /home/osmc/RetroPie-Setup /media/RETROPIE/

Move the rest of the folders to our RetroPie folder on the USB Drive note the capitals as said before…

mv /home/osmc/RetroPie/scripts /media/RETROPIE/RetroPie/
mv /home/osmc/RetroPie/BIOS /media/RETROPIE/RetroPie/
mv /home/osmc/RetroPie/retropiemenu /media/RETROPIE/RetroPie/

Soft system link the rest of the folders as well now.

ln -s /media/RETROPIE/RetroPie/BIOS /home/osmc/RetroPie/BIOS
ln -s /media/RETROPIE/RetroPie/scripts /home/osmc/RetroPie/scripts
ln -s /media/RETROPIE/RetroPie/retropiemenu /home/osmc/RetroPie/retropiemenu

Reboot your RPi via SSH:

sudo reboot

Hopefully that’s it, start it up from the OSMC Programs RetroPie launcher.

Original thread here for further help with other issues: [HowTo] RetroPie and OSMC: Retrosmc - Retrogaming on OSMC


Thanks for your guide. It’s very helpful and detailed.
I’m having a problem at the /home/osmc/install-retrosmc.sh step. The installation kinda works but never shows me the options screen. Afterwards I can’t find the /home/osmc/RetroPie-Setup folder.
I was hoping someone might have some suggestions.

Hi RhinoCoup, what do you mean by “Kinda works” did you make it executable?

Do you not see this

Are you using a strange ssh client?

Do you get any errors, permission denied etc fly by?

1 Like

No clue what was going wrong but it’s resolved itself now and is working perfectly. Thanks you!

Wonderful, the age old, “when all else fails try try again” method, maybe some spotty server connections or something other wise strange, woo hoo!

What if I already have installed OSMC using the install to USB Pendrive method?

I install OSMC with the install to USB option and everything runs off my 1TB USB hard drive perfectly. The only thing the SD card is now used for is booting the PI3 then control is passed onto the USB drive

Its MUCH faster for everything and less strain on the SD card, plus I overclock the RPI3 but do have a BIG heatsink on the CPU and very tiny fan on the case I use so my temps never go much about 45c no matter how hard I push the PI

Its basically the same as setting up RetroPie to run from USB, using the USB transfer option built-in to RetroPie, but this method does it forced manually

If you have installed OSMC with the USB drive method, and install RetroSMC after then it should be alre4ady set-up for USB drive useage. Mine is

Is it possible to install retrosmc in a ext usb in 2019??
I have tried to do it following this instructions and I got some errors in relation to saving the config files

Why do you want the whole installation on ext usb? doesn’t it just need the roms dir to be on ext usb? I have the roms on usb-drive but installation on sd-card.

here’s how i’ve done it

cd ~/RetroPie/roms/
rm -r n64
ln -s /path/to/your/mounted/drive/and/n64/roms/folder/on/it ./n64

(in my case ln -s /media/My\ Book/Jocke/osmc-stuff/disk2/roms/n64 ./n64)

Repeat for any other emulator, remember that the link name got to match the original folder name.

I don’t want the whole installation on ext usb.
As in your case, I would like to have just the roms on ext usb

How should I format the usb drive? EXT4? FAT32?
I think it would be easier in FAT32 to move the roms from my Windows pc

In order to summarize… you remove the “original” directory and after that soft-link this “removed” directory with the one on ext usb??

Regarding formating, exfat is what I would format it with in case you are going to use it on both windows and OSMC-device.

Yes, remove the dir, make a soft link with the “previous folder name”

Then you should be set.

@joakim_s do I have to automount this usb or it is not necessary??

thanks for ur help

well it’s up to you, if you push the USB-drive in it will auto mount under /media. But you can always mount it yourself if you prefer. I thinks it’s easier to just automount and i have my drives attached to my vero 24/7 and i still use automount.

it works flawlessly!!!

1 Like