Add this repo to /etc/apt/sources.list
nano /etc/apt/sources.list
deb http://deb.openswitch.net/stretch 3.2.1 opx opx-non-free
Now run:
sudo apt update
You will receive an error like this:
“The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 5EF20F34AD2074F “
Copy the characters after NO_PUBKEY from the last command and use it below YOUR PUBKEY WILL BE DIFFERENT
apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 5EF20F34AD2074F1
Now that you have the correct signautures your command should be successful
sudo apt update
sudo apt install opx-dell-vm
or depending on what you are doing….
sudo apt install opx-core