yum install clean code example
Example: clear cache yum centos 7
#To clean all cached packages from the enabled repository cache directory
yum clean packages
#To purge the old package information completely
yum clean headers
#To clean any cached xml metadata from any enabled repository,
yum clean metadata
#To clean all the cached files from any enabled repository at once,
yum clean all
#change yum file settings
nano /etc/yum.conf
http_caching=none