RPM Basics

Applies to CentOS Stream 9 & 10 / AlmaLinux 9.x & 10.x / Rocky Linux 9.x & 10.x

RPM (Red Hat Package Manager) is the low-level package management tool for EL systems. While DNF is more commonly used for everyday operations, understanding RPM basics is very helpful for querying package information, verifying package integrity, and troubleshooting issues.

What You Will Learn

• RPM package naming format and structure
• Querying installed package information with rpm
• Installing and verifying RPM files
• The relationship between RPM and DNF
• GPG key verification mechanism

Prerequisites

• A system with EL 9.x installed
• A user account with sudo privileges
• Familiarity with DNF Basics

RPM Package Naming Format

Each RPM package filename follows a fixed format:

name-version-release.architecture.rpm

Using nginx-1.24.0-1.el9.x86_64.rpm as an example:

Part	Value	Description
Name	nginx	Software name
Version	1.24.0	Upstream software version
Release	1.el9	Package release, el9 indicates it is for EL 9
Architecture	x86_64	Target CPU architecture

Note

The architecture noarch means the package is architecture-independent (typically pure scripts or configuration files) and can be installed on any architecture.

RPM Query Operations

RPM’s query capabilities are very powerful and are an essential troubleshooting tool. All query operations begin with rpm -q.

Check Whether a Package is Installed

Check if nginx is installed

$ rpm -q nginx
nginx-1.24.0-1.el9.x86_64

If not installed, the output is:

package nginx is not installed

List All Installed Packages

List all installed RPM packages on the system

$ rpm -qa

Filter with grep

$ rpm -qa | grep ssh
openssh-server-8.7p1-38.el9.x86_64
openssh-clients-8.7p1-38.el9.x86_64
openssh-8.7p1-38.el9.x86_64

Sort by installation time (most recently installed last)

$ rpm -qa --last | head -20

View Detailed Package Information

View detailed information about the nginx package

$ rpm -qi nginx

Example output:

Name        : nginx
Version     : 1.24.0
Release     : 1.el9
Architecture: x86_64
Install Date: Mon 24 Mar 2026 10:00:00 AM CST
Group       : System Environment/Daemons
Size        : 1918738
License     : BSD
Signature   : RSA/SHA256, Fri 15 Nov 2025 08:00:00 AM CST, Key ID ...
Source RPM  : nginx-1.24.0-1.el9.src.rpm
Build Date  : Fri 15 Nov 2025 06:00:00 AM CST
Build Host  : build.almalinux.org
URL         : https://nginx.org/
Summary     : A high performance web server and reverse proxy server
Description : Nginx is a web server and a reverse proxy server...

List Files in a Package

View the files installed by the nginx package

$ rpm -ql nginx

Example output:

/etc/logrotate.d/nginx
/etc/nginx
/etc/nginx/conf.d
/etc/nginx/conf.d/default.conf
/etc/nginx/nginx.conf
/usr/lib/systemd/system/nginx.service
/usr/sbin/nginx
/usr/share/nginx/html/index.html
...

Tip

rpm -ql is particularly useful when you need to find where a specific configuration file is located.

Find Which Package Owns a File

Find which RPM package owns a file

$ rpm -qf /usr/sbin/nginx
nginx-1.24.0-1.el9.x86_64

Find which package owns a configuration file

$ rpm -qf /etc/ssh/sshd_config
openssh-server-8.7p1-38.el9.x86_64

Tip

When you encounter an unfamiliar file, rpm -qf can quickly tell you which package installed it.

List Only Configuration Files

List the configuration files of the nginx package

$ rpm -qc nginx

Example output:

/etc/logrotate.d/nginx
/etc/nginx/conf.d/default.conf
/etc/nginx/fastcgi.conf
/etc/nginx/nginx.conf
...

List Only Documentation Files

List the documentation files of the nginx package

$ rpm -qd nginx

View Package Dependencies

View the dependencies of nginx

$ rpm -qR nginx

View which packages depend on openssl-libs

$ rpm -q --whatrequires openssl-libs

Query an Uninstalled RPM File

Adding the -p parameter to the query commands above lets you query .rpm files that have not been installed:

View information about an uninstalled RPM file

$ rpm -qip ./some-package-1.0-1.el9.x86_64.rpm

List the files contained in an uninstalled RPM file

$ rpm -qlp ./some-package-1.0-1.el9.x86_64.rpm

RPM Query Quick Reference

Command	Description
rpm -qa	List all installed packages
rpm -q <package>	Check if a package is installed
rpm -qi <package>	View detailed package information
rpm -ql <package>	List all files installed by a package
rpm -qf <file-path>	Find which package owns a file
rpm -qc <package>	List a package’s configuration files
rpm -qd <package>	List a package’s documentation files
rpm -qR <package>	View a package’s dependencies
rpm -q --last	List packages sorted by installation time

Installing and Managing RPM Files

Install a Local RPM File

Install a local RPM file using rpm

$ sudo rpm -ivh package-1.0-1.el9.x86_64.rpm

Parameter descriptions:

• -i: Install
• -v: Verbose output
• -h: Show progress bar

Caution

rpm -ivh does not automatically resolve dependencies. If the package has unmet dependencies, the installation will fail. It is recommended to use dnf install ./package.rpm instead, which handles dependencies automatically.

Recommended: Use DNF to Install Local RPMs

Install a local RPM file using DNF (automatic dependency resolution)

$ sudo dnf install ./package-1.0-1.el9.x86_64.rpm

Upgrade an RPM Package

Upgrade an installed package

$ sudo rpm -Uvh package-1.1-1.el9.x86_64.rpm

The -U parameter behavior: if the package is already installed it upgrades; if not installed it installs.

Remove an RPM Package

Remove an installed package

$ sudo rpm -e nginx

Caution

rpm -e also does not handle dependencies. If other packages depend on the package being removed, the operation will fail (unless you use --nodeps, which is strongly discouraged).

Verifying RPM Packages

Verify Installed Package Integrity

Verify whether files from the nginx package have been modified

$ rpm -V nginx

If all files are intact, the command produces no output. If files have been modified, modification markers are displayed:

S.5....T.  c /etc/nginx/nginx.conf

Marker meanings:

Marker	Description
S	File size changed
M	Permissions or file type changed
5	MD5 checksum changed
D	Device number changed
L	Symbolic link changed
U	Owner changed
G	Group changed
T	Modification time changed
P	Capabilities changed

Tip

rpm -V is very useful for security audits. You can verify whether files from critical system packages have been unexpectedly modified.

Verify all installed packages

$ rpm -Va

Note

rpm -Va checks all installed packages and takes a long time to run. Modified configuration files are normal (marked with c); focus on changes to non-configuration files.

GPG Key Verification

RPM uses GPG signatures to ensure package authenticity and integrity.

View Imported GPG Keys

List GPG keys imported into the RPM database

$ rpm -qa gpg-pubkey*

View details of a specific key

$ rpm -qi gpg-pubkey-xxxxxxxx-yyyyyyyy

Manually Import a GPG Key

Import a repository's GPG public key

$ sudo rpm --import https://www.example.com/RPM-GPG-KEY-example

Import a local GPG public key file

$ sudo rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-AlmaLinux-9

Verify an RPM File’s Signature

Verify the GPG signature of an RPM file

$ rpm -K package-1.0-1.el9.x86_64.rpm

Example output (valid signature):

package-1.0-1.el9.x86_64.rpm: digests signatures OK

Example output (invalid signature or key not imported):

package-1.0-1.el9.x86_64.rpm: digests SIGNATURES NOT OK

Caution

After downloading RPM files from the internet, always verify signatures with rpm -K before installing. Installing unverified RPM packages poses a security risk.

The Relationship Between RPM and DNF

Understanding the division of responsibilities between RPM and DNF is important:

Feature	RPM	DNF
Install local .rpm files	Supported	Supported
Automatic dependency resolution	Not supported	Supported
Download and install from repositories	Not supported	Supported
Query package information	Supported	Supported
Verify file integrity	Supported	Not supported
GPG signature verification	Supported	Supported (calls RPM)

In summary:

• DNF is the high-level package manager, responsible for repository management, dependency resolution, and downloading
• RPM is the low-level package manager, responsible for the actual package installation, querying, and verification
• DNF calls RPM under the hood to perform package installation and removal

For daily use, it is recommended to use DNF for installing, updating, and removing packages, and RPM for querying and verification.

Common Issues

rpm -ivh Reports “Failed dependencies”

This means the package has unmet dependencies. Solution:

Recommended: use DNF to install the local RPM

$ sudo dnf install ./package.rpm

Finding Which Package Provides a Command

Use DNF provides to search

$ dnf provides */bin/dig

Example output:

bind-utils-9.16.23-14.el9.x86_64 : Utilities for querying DNS name servers
Repo        : baseos
Matched from:
Filename    : /usr/bin/dig

How to Extract Files from an RPM Package (Without Installing)

Extract files using rpm2cpio

$ rpm2cpio package.rpm | cpio -idmv

Tip

This is useful when you only need a specific file from an RPM package (such as a configuration file template) without installing the entire package.

Further Reading

• DNF Package Management Basics — High-level package management operations
• Repository Management — Manage software repositories
• EPEL and Third-Party Repositories — Access more packages
• man rpm — Complete RPM command reference