yum:tldr:ee6e2

The "yum upgrade" command is used in Linux-based systems that use the Yellowdog Updater Modified (YUM) package manager.

When executed, this command helps to upgrade all packages to their latest available versions. YUM maintains a repository of software packages and their dependencies, and the "yum upgrade" command checks this repository for newer versions of the installed packages.

Here is what happens when you run "yum upgrade":

1. YUM connects to the configured repositories to download the metadata for the available packages and their updates.
2. It checks the metadata against the installed packages on your system to determine if there are any updates available.
3. YUM then prompts you with a list of available updates and asks for confirmation before proceeding with the upgrade.
4. Once you confirm, YUM downloads the updated packages and their dependencies.
5. It then installs the new packages, replacing the older versions on your system.
6. Finally, it updates the relevant configuration files to reflect the changes.

By running "yum upgrade" regularly, you can ensure that your system is up-to-date with the latest bug fixes, security patches, and new features introduced by the software maintainers.