What is rpm?

RPM Package Manager (RPM)

RPM stands for RPM Package Manager (originally Red Hat Package Manager). It's a powerful command-line driven package management system capable of installing, uninstalling, verifying, querying, and updating computer software packages. RPM is used extensively in Linux distributions like Red Hat, Fedora, CentOS, and SUSE, although it's also available for other systems.

Here's a breakdown of important aspects of RPM:

• Purpose: RPM is designed to make software installation and management easier and more consistent. It bundles software, dependencies, and installation instructions into a single file, making it simple to distribute and install software.

• Package Format: RPM packages have a .rpm extension. The file contains the software itself, metadata about the software (name, version, vendor, description, dependencies), and scripts to be executed during installation, uninstallation, and upgrading.

• Key Functionality:

  • Installation: Installing new software packages.
  • Uninstallation: Removing installed software packages.
  • Querying: Retrieving information about installed or uninstalled packages, such as version, dependencies, and file lists.
  • Verification: Checking the integrity of installed packages and verifying that the files haven't been tampered with.
  • Updating: Upgrading existing software packages to newer versions.

• Dependencies: RPM tracks dependencies between packages, ensuring that all required libraries and other software components are installed before a package is installed. This helps prevent software from failing due to missing dependencies. The RPM system will try to resolve the dependencies but sometimes requires external tools like yum or dnf to assist.

• Command-Line Tool: The primary tool for interacting with RPM packages is the rpm command-line utility. It offers various options for performing different package management tasks.

• Package Managers (Frontend Tools): While rpm is the core tool, package managers like yum (Yellowdog Updater, Modified) and dnf (Dandified Yum) provide a higher-level interface that simplifies dependency resolution and package management. These tools automatically download and install dependencies from software repositories.

• Software Repositories: RPM relies on software repositories, which are online collections of RPM packages. Package managers use these repositories to find and download packages and their dependencies. Repositories are defined in configuration files, usually located in /etc/yum.repos.d/ (for yum and dnf).

• Use Cases:

  • Installing and managing software on RPM-based Linux distributions.
  • Distributing custom software packages within an organization.
  • Building and deploying software applications.

• Limitations: RPM primarily deals with package installation and management. It doesn't automatically handle configuration management or service management after installation.