Multiple printers, USB doesn't recognize all of them

Good evening, I followed the tutorial of Chris's, the whole first part went well, three printers declared, but when it is necessary to declare the USb, the command "cat dmesg" does not exist apparently in this version.
I am in Octoprint version 1.3.10 Octopi 0.16.0, all on a raspberry PI 3B +
USB printer on raspberry and connection of raspberry to pc in wifi
Thank you for your help because I am blocked

the link of the video:

6 posts were merged into an existing topic: Multiple printers per Pi megathread