Ubuntu Package Management

# Install a package
apt install <package>
 
# Reinstall a package
apt reinstall <package>
 
# Reinstall a package with all dependencies
apt reinstall <package> $(apt-cache depends --recurse --installed <package> | grep '[ ]')
 
# Remove a package (keeps configuration files)
apt remove <package>
 
# Remove a package and all configuration/data files
apt purge <package>
 
# Upgrade a specific package
apt upgrade <package>

# Update package lists
apt update
 
# Upgrade all packages (safe upgrade - no removals)
apt upgrade
 
# Upgrade with package additions/removals (check carefully)
apt dist-upgrade

# Search for packages by name/description
apt search <string>
 
# Search with scrollable output
apt search <string> | less
 
# Search only by package name
dpkg-query -l '*<string>*'
 
# Search for files within packages (requires apt-file)
apt-file search <filename>
 
# List contents of a package without installing
apt-file list <packagename>
 
# Update apt-file database
apt-file update

# List all installed packages
dpkg --list
# or
apt list --installed
 
# List files installed by a package
dpkg -L <package>
 
# Find which package a file belongs to
dpkg -S /path/to/file
 
# Find package dependencies
apt-cache rdepends <package>
 
# Reconfigure an installed package
dpkg-reconfigure <package>

# Delete all cached package files
apt clean
 
# Delete only outdated cached packages
apt autoclean
 
# Backup installed package list
dpkg --get-selections > package-selections.txt
 
# Restore packages from backup list
apt install $(cat package-selections.txt | awk '{print $1}')
 
# Simulate operations without making changes
apt --simulate upgrade