It looks like the XML libvirt got from vdsm was wrong. Vdsm turns off automatic disk leases and so it is supposed to explicitly configure leases for all read/write disks used by a domain. The "Read/write, exclusive access, disks were present, but no leases specified" error is reported when there are read/write disks attached to a domain but there are no leases configured for them. Can you get the XML vdsm uses for the domain?

I talked to Federico from RHEV storage team and apparently vdsm is configuring libvirt (in /etc/libvirt/qemu-sanlock.conf) so that

auto_disk_leases = 0
require_lease_for_disks = 0

However, the reported error message should only be reported if

auto_disk_leases = 0
require_lease_for_disks = 1

and there are no leases in domain XML.

That said, this looks like someone changed require_lease_for_disks to 1. Michael, can you check if that's the case?

I will ask customer for it now.

Customer has closed the case and not provided the info requested. He has updated to the latest iso and says he does not see same behaviour. We can close this bug. Thank you for the help.

Thanks, I assume the problem was in wrong configuration of libvirt and whatever caused it is now gone.