With Red Hat Enterprise Virtualization, the RHEV Manager can manage two different types of KVM hypervisor hosts:
- RHEV Hypervisor (RHEV-H) — slimmed-down to run just the KVM Linux kernel modules and supporting services
- Red Hat Enterprise Linux 5.4 (RHEL) — full installation with any applications, GUIs, or tools desired
By paying $749/socket for RHEV, users are entitled to use RHEV-H for no additional cost. However, those that opt to use the full installation of RHEL 5.4 must purchase an appropriate RHEL subscription separately, which typically runs $1299-$2499 per host.
Wow, the cost of all this open source virtualization technology can really add up!
Red Hat Enterprise Confusion
A full installation of RHEL 5.4 provides necessary KVM Linux kernel modules and some basic management tools to create and run virtual machines — without a trace of RHEV:
However, don’t jump to the conclusion that such a RHEL 5.4 host can also be managed by the RHEV Manager — the KVM packages required by RHEV are different and incompatible with those provided in a standard RHEL 5.4 installation. In fact, for some odd reason, even the command-line tools are unavailable or incompatible with RHEV — the only way to manage virtual machines is with the RHEV Manager.
Don’t just take my word for it, the Installation Guide says it best:
And don’t forget, the RHEV Manager runs exclusively on Windows and the only interface is Internet Explorer. So much for open source virtualization management technologies.
VMware vSphere Consistency
One of the great strengths of VMware ESXi is the consistent management experience across a range of deployment options. This is because the same exact bits are used for every edition of VMware ESXi — features are simply added by applying appropriate licensing. In fact, the same exact vSphere Client connects to every edition of ESXi — from free to Enterprise Plus — as well as to VMware vCenter Server for centralized management. This design offers a consistent virtualization management experience in every environment.
Red Hat Enterprise Virtualization offers no free edition and expects customers to contend with multiple incompatible variations of the same core hypervisor — each with a different management interface. Somehow, I doubt that is what “customers are asking for.”
Treat your Red Hat Enterprise Linux workloads to the best — run them on VMware vSphere.