Hello all!

First things first - this is all very new to me. I'm doing some work that will utilize ROS quite heavily. In order to set myself up for this, I have configured my machine to dual-boot Windows & Linux - all seems to be working fine so far! However, I know little to nothing about Linux and so I just installed an apparently recent & user-friendly version. I am running Linux Mint 20 "ulyana" with the Cinnamon desktop. Apologies if that doesn't actually make sense and I'm mixing my words around a bit - hopefully you get the idea!

ANYWAY, I'm now trying to get ROS installed, but I'm encountering some issues. I understand that ROS is directly compatible with Linux, and I've come across multiple forums surrounding installing on Linux Mint. I've been following the install instructions at http://wiki.ros.org/noetic/Installati... and I encounter some errors that prevent me from completing the process:

sudo sh -c 'echo "deb http://packages.ros.org/ros/ubuntu $(lsb_release -sc) main" > /etc/apt/sources.list.d/ros-latest.list'

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sudo apt-key adv --keyserver 'hkp://keyserver.ubuntu.com:80' --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654

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Executing: /tmp/apt-key-gpghome.t6CY5ICO3t/gpg.1.sh --keyserver hkp://keyserver.ubuntu.com:80 --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654 gpg: key F42ED6FBAB17C654: "Open Robotics info@osrfoundation.org" not changed gpg: Total number processed: 1 gpg: unchanged: 1

sudo apt update

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Hit:1 http://archive.canonical.com/ubuntu focal InRelease Hit:2 http://archive.ubuntu.com/ubuntu focal InRelease Get:3 http://archive.ubuntu.com/ubuntu focal-updates InRelease [111 kB] Hit:4 http://dl.google.com/linux/chrome/deb stable InRelease Get:5 http://security.ubuntu.com/ubuntu focal-security InRelease [107 kB] Get:6 http://archive.ubuntu.com/ubuntu focal-backports InRelease [98.3 kB] Ign:7 http://packages.linuxmint.com ulyana InRelease Hit:8 http://packages.linuxmint.com ulyana Release Ign:9 http://packages.ros.org/ros/ubuntu ulyana InRelease Ign:10 http://packages.ros.org/ros2/ubuntu ulyana InRelease Err:11 http://packages.ros.org/ros/ubuntu ulyana Release 404 Not Found [IP: 64.50.236.52 80] Err:12 http://packages.ros.org/ros2/ubuntu ulyana Release 404 Not Found [IP: 64.50.236.52 80] Reading package lists... Done E: The repository 'http://packages.ros.org/ros/ubuntu ulyana Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. E: The repository 'http://packages.ros.org/ros2/ubuntu ulyana Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.

Above are my entries and the response from the terminal. Seems the error primarily relates to my release (ulyana) - I've had a look through that packages URL and confirmed that ulyana isn't in the release list. Now here's where my ignorance shines through. I've heard that Linux releases are based on Ubuntu releases, and this is how some of the other Mint users have solved their problems - by substituting '* release' with the corresponding ubuntu codename. I can't seem to find anything about the release that ulyana is based on and so I can't try this myself.

My leaning is that since this is such a new Mint release, perhaps ROS simply does not support it yet? If this is the case it's on me for rushing at the first Linux release I saw, I suppose! And if this is true, is there a way I can simply move to a Linux release that is supported? Will I have to do an entire re-install?

Again, apologies if some of the technical terms are a bit muddled around or incorrect - I'm still trying to get the hang of it all!

Any help greatly appreciated :)

Thanks!

deb http://packages.ros.org/ros/ubuntu focal main