How create a posbox image on a Ubuntu SSH?

Adrien Fidanza

Hello everyone, I explain my problem. I have currently created an Odoo community server v12.0 hosted on a vps at ovh based on ubuntu v18.04. I now want to create a virtual posbox as it is written on the guide available on odoo entitled "Posboxless". Unfortunately I do not find it clear and I can not find the different steps that I must follow to install a posbox image on my ssh ubuntu. Can you help me or give me a starting point for me to know where to go?
Thank you in advance.