Presence of this README indicates that an unmaintained version of Gluster was
enabled on this system. The centos-release-gluster-legacy package caused the
removal of centos-release-gluster* versions that do not receive updates
anymore.
It is strongly recommended to follow the releases for Gluster deployments and
plan for upgrades accordingly. An announcement is sent to the CentOS Announce
and Gluster Announce mailinglists when a new version becomes available.
More details about the versions and their End-Of-Life dates are on
https://www.gluster.org/community/release-schedule