We plan to migrate from OpenStack zu OpenNebula. Currently we use CentOS 7 with elrepo-Kernel (currently 4.4). For our new deployment we are evaluating which OS is the best for our cloud.
Our main concern is the kernel as Ceph is our storage backend, which likes recent versions. A recent version of KVM/QEMU is also appreciated (stable > features).
The team managing our infrastructure has a lot of knowledge of CentOS / RHEL and Debian.
Debian also has a recent 4.9 Kernel but has less intregrated update-management tools like Spacewalk for CentOS / RHEL.
Which OS are you using?