Here is two useful commands to display all the installed packages and version in your RHEL/CentOS Linux system.
1. Display a comprehensive and formatted list using Yum :
yum list installed | more
2. Display the list of RPM package with their full name :
rpm -qa --qf "%{NAME}-%{VERSION}-%{RELEASE}.%{ARCH}\n"
TIP : The suggestion #2 is a good way to provision a new system with the same installed softwares and version. To make this list usable with Yum, just open it in Vi text editor and do the following command :
:j
This will make a continuous text string with your package list name, you just have to prepend “yum install”.