sudo apt-get install <package name>
sudo apt-get install ./***.deb

apt-cache search <search_term>

See details on https://help.ubuntu.com/community/AptGet/Howto

apt --installed list

See details on http://askubuntu.com/questions/17823/how-to-list-all-installed-packages

1. Check disk space by df -h
2. Check kernel images by dpkg -l | grep linux-image
3. Check current kernel by uname -r
4. Clean other kernel by sudo apt-get purge linux-image-3.5.0-{17,18,19,21,22,23,24}-generic

• Do not include current kernel
• Do not include target kernel
• Keep at least one old kernel

See details on http://askubuntu.com/questions/298487/not-enough-free-disk-space-when-upgrading

sudo apt-get update
sudo apt-get upgrade
sudo apt-get autoremove
sudo do-release-upgrade

See details on:

• http://askubuntu.com/questions/462449/update-the-system-from-terminal
• https://help.ubuntu.com/lts/serverguide/installing-upgrading.html

• Install Nexus on Windows
• In Linux
  • Register apt repo
  • Add docker apt repo PGP file
  • Add /etc/apt/sources.list

sudo add-apt-repository "deb [arch=amd64] http://<ID>:<PWD>@<Nexus IP>:<Nexus Port>/repository/download.docker.com/ focal stable"