Red Hat Enterprise Linux 6 is at the end of its life. Therefore it is more important than ever to move your workloads into a supportable state. The redhat-upgrade-tool provides you the mechanism you need to start running RHEL 7 while maintaining your customizations, configurations, and preferences.

 

Learn more: 

https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html-single/upgrading_from_rhel_6_to_rhel_7/index