How to play with YUM

How to use the yum command to update and patch RHEL? Package managers for Linux are tools or software applications that allow users to install, uninstall, update, configure and manage software packages on Linux.

YUM (YellowDog Updater Modified) is the command line package management utility to manage Linux RPM software packages. Yum evolved from Yellow Dog updater (aka “Yup”) which was part of the Yellow Dog Linux distribution for Macintosh computers. yup ran only on Yellow Dog (Macintosh) systems. Yum evolved from Yellowdog Updater(YUP). YUP was created between 1999–2001 to serve as a back-end engine for Linux’s graphical installer.

Then why do we need to use YUM over RPM?

YUM and RPM are package managers, the biggest drawback for RPM is that it cannot resolve package dependencies, for this amongst many other reasons YUM was created.

How do we know where we download files?

The [repository] sections, where the repository is a unique repository ID such as my_personal_repo (spaces are not permitted), allow you to define individual Yum repositories.

You can go to /etc/yum.repos.d to find the repositories defined of where you can download the packages and other security things like GPG key, SSL certs, and so forth.

You can also do repoquery -i {package name} or yum list {package name} or rpm -qi {package name} to understand which repo has been used to install the package you…