How To Install pam_ssh on CentOS 8

pam_ssh is PAM module for use with SSH keys and ssh-agent

Introduction

In this tutorial we learn how to install pam_ssh on CentOS 8.

What is pam_ssh

This PAM module provides single sign-on behavior for UNIX using SSH keys. Users are authenticated by decrypting their SSH private keys with the password provided. In the first PAM login session phase, an ssh-agent process is started and keys are added. The same agent is used for the following PAM sessions. In any case the appropriate environment variables are set in the session phase.

We can use yum or dnf to install pam_ssh on CentOS 8. In this tutorial we discuss both methods but you only need to choose one of method to install pam_ssh.

Install pam_ssh on CentOS 8 Using dnf

Update yum database with dnf using the following command.

sudo dnf makecache --refresh

The output should look something like this:

CentOS Linux 8 - AppStream                                       43 kB/s | 4.3 kB     00:00    
CentOS Linux 8 - BaseOS                                          65 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - ContinuousRelease                               43 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - Extras                                          23 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - FastTrack                                       40 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - HighAvailability                                36 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - Plus                                            24 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - PowerTools                                      50 kB/s | 4.3 kB     00:00    
Extra Packages for Enterprise Linux Modular 8 - x86_64           13 kB/s | 9.2 kB     00:00    
Extra Packages for Enterprise Linux 8 - x86_64                   24 kB/s | 8.5 kB     00:00    
Metadata cache created.

After updating yum database, We can install pam_ssh using dnf by running the following command:

sudo dnf -y install pam_ssh

Install pam_ssh on CentOS 8 Using yum

Update yum database with yum using the following command.

sudo yum makecache --refresh

The output should look something like this:

CentOS Linux 8 - AppStream                                       43 kB/s | 4.3 kB     00:00    
CentOS Linux 8 - BaseOS                                          65 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - ContinuousRelease                               43 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - Extras                                          23 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - FastTrack                                       40 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - HighAvailability                                36 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - Plus                                            24 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - PowerTools                                      50 kB/s | 4.3 kB     00:00    
Extra Packages for Enterprise Linux Modular 8 - x86_64           13 kB/s | 9.2 kB     00:00    
Extra Packages for Enterprise Linux 8 - x86_64                   24 kB/s | 8.5 kB     00:00    
Metadata cache created.

After updating yum database, We can install pam_ssh using yum by running the following command:

sudo yum -y install pam_ssh

How To Uninstall pam_ssh on CentOS 8

To uninstall only the pam_ssh package we can use the following command:

sudo dnf remove pam_ssh

pam_ssh Package Contents on CentOS 8

/lib64/security/pam_ssh.so
/usr/lib/.build-id
/usr/lib/.build-id/49
/usr/lib/.build-id/49/59fde241cb45ddc94a00b40e9b08cc58d586f3
/usr/lib/tmpfiles.d/pam_ssh.conf
/usr/share/doc/pam_ssh
/usr/share/doc/pam_ssh/AUTHORS
/usr/share/doc/pam_ssh/ChangeLog
/usr/share/doc/pam_ssh/NEWS
/usr/share/doc/pam_ssh/README
/usr/share/doc/pam_ssh/TODO
/usr/share/licenses/pam_ssh
/usr/share/licenses/pam_ssh/COPYING
/usr/share/man/man8/pam_ssh.8.gz
/var/run/pam_ssh

References

Summary

In this tutorial we learn how to install pam_ssh on CentOS 8 using yum and dnf.