X Mode or text Mode for a laptop screen with attached Plugable seat(s)


#1

All the Fedora linux multiseat examples I have seen show each seat built around a Plugable unit. Can you attach a plugable seat to a laptop and run x on both the builtin display and attached plugable seat? Is the Laptops internal display limited to text Mode, while plugable seats are attached?

I understand a Text mode " console " login would use less system horsepower. Must one choose Single Seat, Console X, or Multiseat Plugable X. I am new to Linux. I don’t know if Plugable X seats can run alongside Old school, Console x. The Power of a plugable Seat is clear, within the limits of USB 2.0 I/O. What remains unclear is one can do on the original, built-in keyboard and screen. Must one lose MultiSeat attachments to watch video on the builtin Screen?


#2

Hi Jeffrey,

Thanks for asking! What you would expect is that you would have your “built-in” seat (built-in GPU-attached display, keyboard, mouse), and then by adding a USB-attached seat (a Plugable http://plugable.com/products/dc-125/ or http://plugable.com/products/ud-160-m/) would get a 2nd login screen.

Unfortunately, our experience is that the primary seat works on some systems, but not others. For reliability, you’ll want to go with al -USB terminals, and leave the primary display as a console for error logs and administration.

What’s happening on some systems is seat0 (the primary, built-in seat) launches X + GDM as expected, however on others seat0 drops to a text mode console either immediately, or when an error occurs.

We don’t know why results haven’t been consistent – the cause seems to be a combination of DRM vs. fbdev driver issues, fbcon issues, and different updated versions of Fedora 17 components.

So if you’re deploying on Fedora 17 now, to make sure everything is consistent, we have to recommend using your primary display as a administrative console, and have all your real users on USB terminals. That’s kind of conceptually cleaner anyway.

Hope that helps. Thanks again for asking!
Bernie


#3

I thought something must break mixed console x and plugable x configurations. I wonder how Fedora 17 runs under VirtualBoX, VMware, etc? Can you run a MultiSeat Fedora guest under a VM. This would create a MultiSeat subsystem within a Linux, Mac, or even Windows Host. It would also allow the Host to run a different DE / distro from the Mutliseat Fedora. There are clear USB I/o issues, but the VM isolates Fedora from any conflicts with the Hosts hardware, OS, or windowing system. OSx or Windows are single seat only until a good Multiseat Fedora Vm is loaded.


#4

Hi Jeffrey,

Running multiseat out of a Fedora 17 install in a VM doesn’t work well, because F17’s multiseat support is looking for a hub+display+keyboard+mouse clustered together in the USB topology.

The way most Virtual machine software works, you can re-assign individual devices from the host to guest OS, but you can’t re-assign a hub and all its children in one go (and have it keep that topology intact).

If you found virtual machine software that did that, it would work. But I’m not aware of any.

Thanks!
Bernie


#5