RPM - RedHat Package Manager

RPM (RedHat Package Manager) is a powerful package management system originally developed by Red Hat for Linux distributions. It provides a standardized method for software installation, upgrade, removal, and verification across RPM-based Linux systems.

Overview

RPM packages contain compiled software along with metadata, dependency information, and installation scripts. The RPM system ensures consistent software deployment and management across Red Hat Enterprise Linux, CentOS, Fedora, SUSE, and many other Linux distributions.

File Characteristics

• File Extension: .rpm
• MIME Type: application/x-rpm
• Format: Binary package archive
• Compression: GZIP, BZIP2, or XZ compression
• Architecture: Platform-specific binaries

Package Structure

Header Section

• Package metadata and information
• Dependency requirements
• Installation scripts
• File listing and attributes

Payload Section

• Compressed archive of files
• Binary executables and libraries
• Configuration files
• Documentation

RPM Package Naming Convention

package-version-release.architecture.rpm

Examples:

• httpd-2.4.41-34.el8.x86_64.rpm
• kernel-5.4.0-42.generic.x86_64.rpm
• vim-common-8.2.1-1.fc33.noarch.rpm

Components

• Package Name: Software package identifier
• Version: Upstream software version
• Release: Package build number
• Architecture: Target hardware platform (x86_64, i386, noarch)

Package Management Commands

Installation

# Install a package
rpm -i package.rpm
rpm -ivh package.rpm  # verbose with hash progress

# Install with dependencies (use yum/dnf instead)
yum install package.rpm
dnf install package.rpm

# Force installation (not recommended)
rpm -ivh --force package.rpm

Querying

# List all installed packages
rpm -qa

# Query package information
rpm -qi package-name

# List files in a package
rpm -ql package-name

# Find which package owns a file
rpm -qf /path/to/file

# Query package from file
rpm -qip package.rpm

Upgrading

# Upgrade a package
rpm -U package.rpm
rpm -Uvh package.rpm

# Freshen (upgrade only if already installed)
rpm -F package.rpm

Removal

# Remove a package
rpm -e package-name

# Remove with no dependency checking (dangerous)
rpm -e --nodeps package-name

Verification

# Verify all installed packages
rpm -Va

# Verify specific package
rpm -V package-name

# Verify package files
rpm -Vf /path/to/file

RPM Database

Database Location

• /var/lib/rpm/ - RPM database directory
• Contains package information and file ownership data
• Berkeley DB format (traditionally)

Database Maintenance

# Rebuild RPM database
rpm --rebuilddb

# Initialize new database
rpm --initdb

# Check database consistency
rpm -vv --rebuilddb

Spec File Format

RPM packages are built from spec files that define the build process:

Name:           mypackage
Version:        1.0.0
Release:        1%{?dist}
Summary:        A sample package

License:        GPLv3+
URL:            http://example.com/mypackage
Source0:        %{name}-%{version}.tar.gz

BuildRequires:  gcc
Requires:       glibc

%description
This is a sample package for demonstration purposes.

%prep
%setup -q

%build
make %{?_smp_mflags}

%install
rm -rf $RPM_BUILD_ROOT
make install DESTDIR=$RPM_BUILD_ROOT

%files
%doc README
%{_bindir}/myprogram
%{_mandir}/man1/myprogram.1*

%changelog
* Thu Jan 01 2024 Developer <[email protected]> - 1.0.0-1
- Initial package

Spec File Sections

• %prep: Prepare source code for building
• %build: Compile the software
• %install: Install files to build root
• %files: List files to include in package
• %pre/%post: Pre/post installation scripts
• %preun/%postun: Pre/post uninstallation scripts

Building RPM Packages

Build Environment Setup

# Install development tools
yum groupinstall "Development Tools"
yum install rpm-build rpmdevtools

# Set up build environment
rpmdev-setuptree

Build Process

# Build from spec file
rpmbuild -ba mypackage.spec

# Build binary RPM only
rpmbuild -bb mypackage.spec

# Build source RPM only
rpmbuild -bs mypackage.spec

# Build from source RPM
rpmbuild --rebuild mypackage.src.rpm

RPM Macros

Common Macros

• %{_prefix} - Installation prefix (usually /usr)
• %{_bindir} - Binary directory (/usr/bin)
• %{_libdir} - Library directory (/usr/lib64)
• %{_sysconfdir} - Configuration directory (/etc)
• %{_mandir} - Manual page directory (/usr/share/man)

Custom Macros

%define myvar value
%global myvar value

# Usage
Some text with %{myvar} substitution

Dependency Management

Automatic Dependencies

RPM automatically detects:

• Shared library dependencies
• Script interpreter requirements
• Binary dependencies

Manual Dependencies

Requires: package >= version
BuildRequires: package-devel
Conflicts: conflicting-package
Obsoletes: old-package-name

Virtual Dependencies

Provides: virtual-package
Requires: virtual-package

RPM Security

Package Signing

# Import GPG key
rpm --import RPM-GPG-KEY-distname

# Verify package signature
rpm -K package.rpm
rpm --checksig package.rpm

# Install only signed packages
rpm -ivh --nosignature package.rpm  # skip signature check

Package Verification

# Verify package integrity
rpm -V package-name

# Check file checksums
rpm -Va --nosize --nouser --nogroup --nomtime

Distribution-Specific Tools

Red Hat/CentOS

• yum: Traditional package manager
• dnf: Modern package manager (Fedora/RHEL 8+)
• subscription-manager: Red Hat subscription management

SUSE

• zypper: Package management tool
• YaST: System administration tool

Fedora

• dnf: Default package manager
• PackageKit: Desktop package management

Best Practices

Package Building

1. Follow FHS: Adhere to Filesystem Hierarchy Standard
2. Proper Dependencies: Specify accurate requirements
3. Clean Builds: Ensure reproducible builds
4. Documentation: Include comprehensive package documentation
5. Testing: Thoroughly test packages before distribution

System Administration

1. Regular Updates: Keep packages current for security
2. Backup Before Changes: Create system backups
3. Test Updates: Validate updates in non-production environments
4. Monitor Dependencies: Be aware of package relationships
5. Use Repositories: Prefer repository installation over individual RPMs

Troubleshooting

Common Issues

• Dependency conflicts
• Package corruption
• Database corruption
• Installation failures

Resolution Strategies

# Fix broken dependencies
yum-complete-transaction
package-cleanup --problems

# Clean package cache
yum clean all
dnf clean all

# Force package reinstallation
rpm -e --nodeps package-name
yum reinstall package-name

RPM remains a cornerstone technology for Linux system administration, providing robust package management capabilities essential for enterprise Linux deployments.