clear cache yum centos 7

C++
#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
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