Installing LinuxCNC 2.8 on Debian 11

Looks like there's a dependency issue with ghostscript:

sysadmin@cnc1:~$ uname -a
Linux cnc1 5.10.0-10-rt-amd64 #1 SMP PREEMPT_RT Debian 5.10.84-1 (2021-12-08) x86_64 GNU/Linux
sysadmin@cnc1:~$ sudo apt install libudev-dev bwidget intltool libboost-python-dev libepoxy-dev libgl1-mesa-dev libgtk2.0-dev libgtk-3-dev libmodbus-dev libeditreadline-dev libtk-img libusb-1.0-0-dev libxmu-dev netcat python3-dev python3-xlib tcl8.6-dev tclx tk8.6-dev yapps2 asciidoc dblatex docbook-xsl dvipng groff imagemagick inkscape python3-lxml source-highlight w3c-linkchecker xsltproc texlive-extra-utils texlive-font-utils texlive-fonts-recommended texlive-lang-cyrillic texlive-lang-french texlive-lang-german texlive-lang-polish texlive-lang-spanish texlive-latex-recommended asciidoc-dblatex texlive-xetex
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'tclx8.4' instead of 'tclx'
python3-dev is already the newest version (3.9.2-3).
python3-dev set to manually installed.
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
dvipng : Depends: ghostscript but it is not installable
E: Unable to correct problems, you have held broken packages.

oops, nvm, it turns out the /etc/apt/sources.list needs to have the security repository added so it looks like this:
 

Just to be clear - these are instructions on how to install 2.9, NOT 2.8 as it says in the title

I'm sorry, it wasn't intentional, can you help me?

Hahhaha, I felt the same way I first took a look at this LinuxCNC stuff.  Everybody is like screw you RTFM. That's why you won't get any actual answers.  Here's the juicy secret that nobody tells you:

1) you CAN'T install linuxcnc 2.8 on Debian 11. Dependencies are broken.

2) You CAN install linuxcnc 2.9 on Debian 11. Unfortunately, v2.9 is bleeding edge and so the only way to install it is to compile it from source code. If you are not used to compiling software from source, it's gonna be EXTREMELY PAINFUL

So, to answer your question, <sarcasm> NO THERE IS NO STEP BY STEP FOR THIS, RTFM!!! Go play in with your toys in the sandbox and just download the ISO image for 2.8 and Debian 10 and install it like this:</sarcasm>

P.S., if you want a sure-fire way to get an actual answer to any forum anywhere, just post something that sounds like you totally know what you are doing but could be completely wrong.  If it's wrong, it will be in the very next post.  If it's right, you'll hear crickets.  Let's see what the next post is in response to number 1) above.....
 

1) you CAN'T install linuxcnc 2.8 on Debian 11. Dependencies are broken.
how do you get that idea?

I must admit I forgot that the question was how to install linux2.8 on Debian 11 (Bullseye).

In short.... you can't. Its not because the dependancies are broken but Debian has moved on from Python2 >> Python 3 so I don't believe that you can install Python2 on debian 11 (bullseye).
wiki.debian.org/Python


Just install 2.8.2 from the ISO if you are new to linuxcnc and it WILL work just fine. If you want to be one the bleeding edge of linuxcnc then yet you will need to compile linuxcnc.... not it's not difficult or complicated.
Here is how to do it.... but yes you do need to RTFM.... or else you won't actually learn how linuxcnc actually works and what it needs to make it work.
linuxcnc.org/docs/devel/html/code/building-linuxcnc.html

first open up a terminal

and install git and dpkg-dev
then download linuxcnc from git:
then find out the missing dependancies:
then run:
then change to the linuxcnc-dev directory:
then run the following to find all missing build dependancies and install them:
Once you have installed all the missing dependencies then re-runin order to check that there are no more missing dependancies. If anything is missing, install it or linuxcnc won't build.

then I would recommend building the debs to install....
linuxcnc.org/docs/devel/html/code/buildi...ding_debian_packages
then run each of the following lines.
once the build is complete then:
there are many links on the forum as to how to install linuxcnc so really you do need to RTFM

I have never thought of V 2.9 as bleeding edge. I have used master branch since my very first build becasue it had features I needed.

A shortcut to the installation Robert provided is to use Joco's script to install and build linuxcnc on a bullseye PC
github.com/joco-nz/lcnc-bullseye-installer

The other possibly even quicker way might be to install the brand new deb file on the debian repositories
packages.debian.org/sid/linuxcnc-uspace
Not sure if it will work with bullseye
In a few days it will be in  the yet to be released Debian 12 Bookworm (also known as testing). From that point on I won't be bothering with Bullseye/Debian 11 and will go straight to Bookworm

RJ11:

Yeah if you post waste products of the bovine community you'll be corrected, when you're actually correct people will just nod in agreement. This has been pretty much how humanity has worked since day one.

You know it's pretty disrespectful to ignore the Docs. The devs put a lot of time into writing and fine tuning them. It's amazing what you find out by actually reading the manual, you'd be surprised. Personally if an answer to a question is better described in the docs than I can do, I'll link to the docs. It's far easier to link to the docs than spend 10 - 15 minutes typing up an answer. If the docs aren't clear in a section, ask a question addressing that issue.

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

I think you'll find there are systems out there running Wheezy & even early Ubuntu just fine. The hackers haven't taken over there machines, the world hasn't ended or anything like that.

Distributions move on, software releases move on, there's nothing new about this, it's just the way it is. This happens no matter what the OS.

Compiling Linuxcnc is not a pain. Once you have all the deps it's easy (this is a once off task). All your doing is typing in a few commands. Obviously you've never used Slackware. hahahaha

You guys might like to try this shortcut

download and install debian 11 Bullseye from an official ISO
open a terminal
add these lines (control-shift-v will paste text into nano)

Save the file and exit

I tried this on my chromebook and it worked but I could not check that the preempt_rt kernel was installed even though I saw it downloaded. Not sure if you need to update grub to boot into preempt_rt but the last 2 Debian 11 installs I've done booted into preempt_rt without any action on my part

Note that in a week or so the linuxcnc package will migrate  into testing branch (debian 12). When this happens, change the sources b replacing unstable with testing.