Hi,
I have been using a pxe-bootin Rpi 3 for with usbip to connect my prusa MK3 to a vm running octoprint.
But some times I am having network issues and the print stops/fails.
Now I am asking myself for the cheapest way to connect the MK3 to the VM.
Does anyone have ideas for the cheapest way for this?
Best regards and thanks in advance,
Otto
Hello @otto001 !
Running OctoPrint on a VM is basically a bad idea.
Due to the processing of serial ports (Ethernet as well as USB) by the VM, there appear to be lags that disturb the proper functionality of OctoPrint.
Also a VM on a SBC makes no sense either. SBCs like the Pi in conjunction with OctoPrint are meant to run alone for that purpose.
An alternative can be Docker.
Hi,
thanks a lot! But I have never had issues with the vm itself. As mentioned, I do not run the printer connected directly to the vm (the vm is running on a server in the basement), but I am using a raspi with usbip to forward USB to the vm. the reason for me doing this is, that I only have a rpi3 for that and the web interface was too slow for me. using the vm it is really, really smooth 
but thanks for your answer!
Best regards,
Otto
I have had your setup in the past... Although I used a pi Zero. Had some similar issues.
I did a lot of searching and even tried a few other devices to connect the serial ports. There are no really simple and inexpensive solutions to use a VM to run OctoPrint reliably. And as I am sure you know.. the more things you have in the setup the more things that can go wrong.
Now I use a mini PC for running Octoprint. Below is little info on the ones I have been using. I have not had any issues with them. They just work out of the box. Well you have to install Octoprint.
At the moment you can get it for ~$100. (note the $40 coupon deal), BTW.. this happens all the time so if not now keep an eye out, it will show up again.
https://www.amazon.com/gp/product/B0BBMMYQNB
It is pretty hard to beat that price and performance with a Pi. By the time you buy all the paraphernalia, you are out more than $100 and you still have to do all the work to put it together.
I normally run 2 instances of OctoPrint on one of these with no performance issues. I am sure you could do more. Just use the script to install your instance. You can use the OS that comes on it. Set up is so painless.
Thanks a lot!
I just bought a used rpi4. lets see. will install octopi on it. should be much more performant than a rpi3 I suppose (at least my video devices are).
its a pity that there is no cheap solution to only forward an usb port... 
The more "things" you place between the gcode source (usually OctoPrint) and the 3d printer (your MK3), the higher the probability that the printed object will have artifacts (or just fail). Applying the K.I.S.S. principle works best for 3D printing.
I have an RPi 3B running OctoPi connected to my LulzBot TAZ 6 with an RPi Camera V2 and I think the performance is totally acceptable. IMO, an RPi 4B or the mini-PC linked above should be more than adequate.
.
Yes, the compute and memory are more than enough.. but do some research and make sure you can install Ubuntu or your (Linux flavor of choice) on it without any special trickery. Sometimes putting a new OS on these cheap systems can be a bit of a challenge. Alternatively you could use it with windows but that will put a good bit more strain on the resources and could matter if you don't know how to manage that.
Something else to note.. it is listed as coming with Windows 10 not 11. that means it is out of date already with the OS if you intend to stick to Windows. It likely does not support windows 11.
