The administrator should check disk space in the /var directory first when using YUM to update applications on a server. YUM stands for Yellowdog Updater Modified, which is a software package manager for Linux systems that use RPM (Red Hat Package Manager) packages. YUM downloads and installs packages from online repositories and resolves dependencies automatically. YUM stores its cache files in the /var/cache/yum directory by default. These cache files include metadata and package data for each repository that YUM uses.
If there is not enough disk space in the /var directory, YUM may fail to update applications and generate error messages.