Installing LinuxCNC 2.8 on Debian 11

I installed as mentioned in forum.linuxcnc.org/9-installing-linuxcnc...an-11?start=0#229433. On Dell optiplex works fine, on MSI PRO 16T 10M there are big delays. Thank you.

 Apart from Bullseye being the latest stable Debian, what is the issue with using Buster for 2.8.
 

Hardware support.  I had a Dell Optiplex 790 that came with an add-in factory parallel port card.  It uses the parport_pc kernel module.  That particular card isn't supported by the 4.x kernel that comes with Debian 10.  Debian 11 has a newer kernel which supports it out of the box, 
 

Rodw's script worked well for me. Thank you!

A couple of questions though:

1.) There were the following other lines in sources.list:

deb deb.debian.org/debian-security/ bullseye-security main
deb-src deb.debian.org/debian-security/ bullseye-security main

deb deb.debian.org/debian bullseye-updates main
deb-src deb.debian.org/debian bullseye-updates main

I tried replacing "bullseye" with "unstable" but apt didn't like this so I just commented them out for the install. But should they be uncommented at this point? If so, should they be modified?

2.) How will I know when to change "unstable" to "testing" and then to something else like "bullseye" when the version becomes stable?

Debian is already informing me of available updates. Do I need to make changes to sources.list before installing these updates?

Thanks as always for your advice!

I changed my process and upgraded to the unstable branch by following some instructions on the Debian site
From a basic install of Debian 11 (Bullseye)make sure any lines containing cd are commented out with a #
replace any reference to bullseye, buster or stable with unstable eg:save and exit geany, thenLast line is to check PREEMPT-RT kernel is running as its installed by the install
Linuxcnc should be in the menus or open a terminal and type:
If you need to update to the latest version of master, you need to install from source but there are far fewer dependencies to install.

Note I did not install the docs as thats quite time consuming and we already have a slightly earlier version of them on the system. If you want them, remove the no-docs flag to ./configure

Optionally install the dev package for mesaflash, halcompile, ethercat etc.

This moved my version of QTplasmac from 1.222.178 when I did it.Note that opening an older sim version of QTplasmac generates an error with a missing .so file for the torch simulation.
The solution is to create a new sim by selecting from the Sample Configurations

To subsequently upgrade to the latest version of linuxcnc masteroptionally

may want to add a -j switch for your dpkg-buildpackage for your number of processors as it will spreed up the build time

in my case -j4

ymmv