Package Management

dpkg

dpkg -l (List packages)

dpkg -l <package> (List packages matching pattern)

• Third character r, or blank, indicates re-installation is required, or not.

dpkg -L <package> (List the files installed by a package)

dpkg -V <package> (Verify package)

dpkg --get-selections (List of all of packages, installed or not, but not purged)

dpkg --get-selections | awk '$2 ~ /^install/' (Shows installed)

dpkg --get-selections | awk '$2 !~ /^install/' (Shows not-installed, but not purged)

dpkg --get-selections <package>

sudo dpkg -i debfile.deb (--install; possibly broken) sudo apt-get install -f (Fix)

dpkg -I debfile.deb (--info)

dpkg -S /path/to/file (--search; which package installed a file)

apt

apt-get

sudo apt-get install package=version

sudo dpkg-reconfigure <package>

apt-get install -s <package> (Dry run)

apt-get download <package> (But, don't install)

sudo apt-get source <package> (Downloads to current directory)

sudo apt-get purge <package> (Removes everything)

sudo apt-get autoremove (Remove any packages that were installed as dependencies that are no longer required by any packages)

sudo apt-get --purge autoremove

sudo apt-get autoclean (Remove any package files on the local system that are associated with packages that are no longer available from the repositories)

apt-cache

apt-cache search <keyword>

apt-cache search -n <keyword> (search name only)

apt-cache pkgnames <keyword> (search name-only)

apt-cache show <package>

apt-cache showpkg <package> (More detail; including reverse dependencies)

apt-cache depends <package>

apt-cache rdepends <package>

apt-cache policy <package> (Indicates version priority; determine if extra repositories or PPAs supersede default repositories)

apt-file

Includes the installation path of every file controlled by a package in the database. For package info without install.

1. sudo apt-get update
2. sudo apt-get install apt-file
3. sudo apt-get update
4. sudo apt-file search /path/to/file

Backup

1. dpkg --get-selections > ~/backup/packagelist.txt (Export the list of installed packages to a file)
2. cp -rp /etc/apt/sources.list* ~/backup (Backup your sources)
3. apt-key exportall > ~/backup/trusted_keys.txt (Backup trusted key list)
4. Backup configuration files you want to save.

Restore

1. sudo apt-key add /backup/trusted_keys.txt
2. sudo cp -r /backup/sources* /etc/apt/
3. sudo dpkg --clear-selections (Mark non-essential packages for deinstallation)
4. sudo apt-get update (Create records for all of the software we want to install)
5. sudo apt-get install dselect (Manages upgrade)
6. sudo dselect update (Build deselect database)
7. sudo dpkg --set-selections < /backup/packagelist.txt
8. sudo apt-get dselect-upgrade (Download and install any necessary packages)
9. Copy configuration files from backup location.

PPA's

sudo add-apt-repository ppa:owner_name/ppa_name sudo apt-get update

Add Repos

In /etc/apt/sources.list.d/new_repo.list

Copy
`deb_or_deb-src url_of_repo release_code_name_or_suite component_names`

OR

sudo add-apt-repository 'deb url release component'

unattended-upgrades

Configure: /etc/apt/apt.conf.d/50unattended-upgrades

The double “//” serve as comments.

Enable: /etc/apt/apt.conf.d/20auto-upgrades (File may not exist)

Numbers indicate frequency in days.

man apt.conf (For more info)

less /usr/lib/apt/apt.systemd.daily (Well documnted)

/var/log/unattended-upgrades (Check log)

Configure Unattended-Upgrade::Mail in /etc/apt/apt.conf.d/50unattended-upgrades to enable email notifications.

Consider installing apticron