Hi,ovirt-release-master enables testing repos from CentOS.
Testing repos are now switching to CentOS 7.5.1804 so you now need to enable also the CR repo when testing master on CentOS.
CentOS 7.5 should be released this week or in worst case next week, so this is just a temporary issue while 7.5 is being rolled out.
oVirt release 4.2 uses stable repos and is not affected by this temporary glitch.
Thanks,
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