Ubuntu 20 04 modifications

Cloud-init

dpkg-reconfigure cloud-init
//disable all but none

apt-get purge cloud-init
rm -rf /etc/cloud/
rm -rf /var/lib/cloud/

Realsense

sudo apt-key adv --keyserver keys.gnupg.net --recv-key C8B3A55A6F3EFCDE || sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-key C8B3A55A6F3EFCDE
sudo add-apt-repository "deb http://realsense-hw-public.s3.amazonaws.com/Debian/apt-repo bionic main" -u

apt install librealsense2==2.34.0-0~realsense0.2251
apt-mark hold librealsense2

optinal

sudo apt-get install librealsense2-dbg

gcc

update-alternatives --remove-all gcc 
update-alternatives --remove-all g++

apt install gcc-7 g++-7 gcc-9 g++-9

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-7 10
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-9 20

sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-7 10
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-9 20

sudo update-alternatives --install /usr/bin/cc cc /usr/bin/gcc 30
sudo update-alternatives --set cc /usr/bin/gcc

sudo update-alternatives --install /usr/bin/c++ c++ /usr/bin/g++ 30
sudo update-alternatives --set c++ /usr/bin/g++

update-alternatives --config gcc
update-alternatives --config g++