While continuing on my way toward getting a fully running RHEV set up on RHEL 7, I find myself facing two new problems. Neither has a simple solution. The first is the lack of support in RHEV for RHEL 7 as a hypervisor. The second concerns a change in Red Hat’s handling of virtualization licenses. Solving these issues will entail making some hard choices or spending lots of money.
RHEV RHEL 7 Support
RHEL 7 as a hypervisor support does not even exist in oVirt (the upstream project for RHEV). I wished to install RHEV in hosted-engine mode. When RHEL 7 came out, I fully expected all of Red Hat’s products to be at the same level and support the latest hypervisors, etc. Granted, OpenStack 4.0 is available, but I wanted to try out oVirt/RHEV and see where I could get. At the time of this writing, my only two options for managing my KVM system(s) are to use virt-manager directly and connect to each hypervisor, or to use something like HotLink to manage my KVM hosts from within VMware vCenter. The second appeals to me, as I have been using vSphere since v1.5; yet, a full Red Hat solution is where I wish to go. When will RHEL 7 as a hypervisor be supported inside oVirt? I have no idea; there is nothing yet that tells me.
So, for RHEV, we are in a wait and see mode.
RHEL 7 Licensing
I run many RHEL virtual machines. I want to upgrade my templates and base images to RHEL 7, so that I have a unified approach to management, but this is not possible yet. Why? Because in order to upgrade to RHEL 7, you need to use Red Hat’s new Subscription Manager within the RHN portal. Subscription Manager works quite a bit differently than the traditional RHN. For one, if you have a Virtual Datacenter license, which used to cover multiple hypervisors, you license per hypervisor. At least, that is what I gather from the current discussion with Red Hat.
A Virtual Datacenter spans hypervisors, so why is it locked to a single hypervisor? This is either a massive oversight within Red Hat or a ploy to make more dollars. I hope it is an oversight. However, what this means is that all those folks who use RHEL within VMware vSphere and other hypervisors, including KVM, will just refrain from switching to RHEL 7 immediately. This will definitely prolong the use of RHEL 6.5 until all the tools and licensing catch up with RHEL 7. The other option is to invest in a RedHat Satellite server, which is fairly pricy but would also solve this problem.
Where Am I Going from Here?
The RHEV Upgrade Saga may be stalled until three things happen:
- RHEV/oVirt supports RHEL 7
- Licensing of RHEL 7 is fixed for Virtual Datacenters (these SPAN hosts are not tied to any given host)
- There is a better way to manage RedHat KVM (perhaps using OpenStack?)
If you want to stay with Red Hat and are currently using RHEV and traditional RHN, you may want to hold off on RHEL 7 until such time as these items are fixed or documented in a better way. I know I have to do so, which will delay my rollout to RHEL 7 for all my virtual machines.