The dpkg (Debian Package Manager) command is used in Debian-based Linux distributions (such as Ubuntu, Debian, and Kali Linux) for installing, removing, and managing .deb packages. Unlike apt, dpkg does not resolve dependencies automatically but provides more low-level package control.

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1. Install a .deb Package

sudo dpkg -i package.deb

✔ What it does:

• -i → Installs the .deb package.
• Does not handle missing dependencies.

📌 Example:

sudo dpkg -i google-chrome-stable_current_amd64.deb

📌 If dependencies are missing, fix them using:

sudo apt-get install -f

💡 Use when manually installing .deb files.

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2. Remove a Package

sudo dpkg -r package-name

✔ What it does:

• -r → Removes a package but keeps its configuration files.

📌 Example:

sudo dpkg -r google-chrome-stable

📌 To remove configuration files as well, use -P:

sudo dpkg -P google-chrome-stable

💡 Use -r for uninstalling but keeping settings. Use -P to erase everything.

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3. List Installed Packages

dpkg -l

✔ What it does:

• -l → Lists all installed packages.

📌 Example Output:

ii  google-chrome-stable  95.0.4638.69-1 amd64
ii  git                   2.34.1         amd64

📌 To check if a specific package is installed:

dpkg -l | grep chrome

💡 Helpful when checking for installed packages before updating or removing them.

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4. Get Information About a Package

dpkg -s package-name

✔ What it does:

• -s → Shows detailed information about an installed package.

📌 Example:

dpkg -s git

📌 Output Example:

Package: git
Status: install ok installed
Version: 2.34.1
Architecture: amd64
Description: Distributed version control system

💡 Useful for checking version, status, and description.

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5. List Files Installed by a Package

dpkg -L package-name

✔ What it does:

• -L → Lists all files installed by a package.

📌 Example:

dpkg -L apache2

📌 Sample Output:

/.
/etc/apache2
/etc/apache2/apache2.conf
/usr/sbin/apache2
/usr/lib/apache2

💡 Helpful for knowing where a package installs its files.

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6. Find the Package That Owns a File

dpkg -S /path/to/file

✔ What it does:

• -S → Finds which installed package a specific file belongs to.

📌 Example:

dpkg -S /usr/bin/git

📌 Output:

git: /usr/bin/git

💡 Useful for identifying which package installed a file.

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7. Reconfigure a Package

sudo dpkg-reconfigure package-name

✔ What it does:

• Reconfigures a package after installation.
• Used to reset settings or fix issues.

📌 Example:

sudo dpkg-reconfigure tzdata

📌 Allows you to select the correct timezone again. 💡 Great for reconfiguring system-wide settings.

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8. Extract .deb Package Without Installing

dpkg-deb -x package.deb output-directory/

✔ What it does:

• -x → Extracts package contents without installing.

📌 Example:

dpkg-deb -x google-chrome-stable_current_amd64.deb chrome-files/

💡 Useful for inspecting package files before installation.

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9. Check if a Package is Installed

dpkg -l | grep package-name

✔ What it does:

• Searches for a package in the installed package list.

📌 Example:

dpkg -l | grep firefox

📌 Output:

ii  firefox  96.0+build1-0ubuntu amd64

💡 Useful for verifying if a package is already installed.

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10. Fix Broken Packages

sudo dpkg --configure -a

✔ What it does:

• Completes installation for partially installed packages.

📌 Example Error:

dpkg was interrupted, you must manually run 'dpkg --configure -a' to correct the problem.

📌 Fix it with:

sudo dpkg --configure -a

💡 Run this if package installation was interrupted.

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Final Thoughts

• dpkg is low-level and does not resolve dependencies automatically (use apt for that).
• It’s useful for managing .deb files manually, checking installation details, and fixing issues.