While I do use Qubes, I also have different hardware for more sensitive projects and a permanently offline machine for extremely sensitive tasks. A KVM switch would really make my life easier (especially because I use multiple monitors), but I cannot find a Qubes-friendly KVM.
I would define this as using PS/2 input and I would subjectively argue for DisplayPort graphics because it’s an open standard. IIRC all Qubes-certified devices offer DisplayPort connectivity.
Some desirable features admittedly influenced by my specific work:
a USB hub
3-4 host machines
5+ displays
Does anyone know of a compatible KVM that has any of this (at a minimum PS/2 connectivity)? Has anyone created his own?
There are a lot of DisplayPort KVM switches out there. The problem I find is that none of them offer PS/2 but USB 2/3. Do you think there are compatible adapters to bridge the USB to PS/2 for each of your machines?
Also, and this is an open question, do you think a KVM switch is a significant risk factor? It could theoretically store all your input and video signals. So you have to trust the device and its firmware.
However, I am looking for something very similar. I plan for 3-4 PCs connected to a single keyboard/mouse connected to 2-3 4K displays.
Yes, I have found one but it was 80USD IIRC (for an active adapter). That’s not a sustainable cost for multiple machines.
Personally, I do since it is imperative for me that the separate machines I use remain separate. The best-case scenario for me would be to build my own KVM, but I have no experience with this.
I could pretty easily build one for two PCs with a single VGA/DVI and PS/2 with a Pi and a breadboard, but (4+1)x6 DisplayPort connectors does not lend itself to easy engineering.
I was also thinking that as a best case I might even make it totally mechanical—have a switch that bridges one PC at a time to one input set at a time. I could put it in a transparent case and that would be best. But alas, DisplayPort does not easily fit into a breadboard, much less 30 of them in a reasonable form factor. I would have to find a board that could support mounting 6x DP to individual wires.
I am also considering doing a KVM-over-IP with RPis, but once again handling 5-6x DP connectors per machine is difficult.
For me, open standards is a must. This is admittedly less for security than personal distaste for proprietary/closed systems, although I see it as an all-around win.
