Earlier in this series on Red Hat Enterprise Virtualization (RHEV), I mentioned the fact that the RHEV Manager (RHEV-M) deploys exclusively on a Windows Server 2003 system and can only be accessed from Internet Explorer. Obviously, this is upsetting to loyal open source enthusiasts, but anecdotal reports indicate Redmond has completely endorsed the strategy.
Red Hat makes some strong claims about RHEV worth scrutinizing:
Compared to the competition feature by feature, Red Hat Enterprise Virtualization offers best-in-class, cutting-edge enterprise virtualization features.
In this article, we’ll take a more detailed look at the RHEV Manager.
It’s The Manager
Make no mistake about it, RHEV-M is not just a manager, it is The Manager for Red Hat Enterprise Virtualization. There are no other interfaces for administrators to create, start, stop, or migrate virtual machines. No command-line utilities and no option for a management client to connect directly to hypervisor hosts.
They could have called it…
Red Hat Enterprise Single-Point-of-Failure
RHEV-M is one seriously mission critical component of the RHEV infrastructure, so it is surprising to see that there are no high-availability options for RHEV-M — no clustering or other redundancy support.
Even the approach of protecting RHEV-M by deploying it in an HA VM is also impossible — something that works just fine for vCenter Server and even System Center VMM. That’s because RHEV-M is the sole management tool for RHEV, creating a chicken-and-egg situation that essentially mandates the use of a physical system.
Red Hat is asking their loyal Linux customer base to deploy a physical Windows box — that is a single point of failure — to manage their open source hypervisor. I did not notice that bullet point on their competitive comparison document.
In fact, Red Hat goes so far as to say:
… today, server virtualization is not used pervasively in the production enterprise datacenter. Some of the barriers preventing wide-spread adoption of existing proprietary virtualization solutions are performance, scalability, security, cost, and ecosystem challenges.
It never occurred to me that VMware, the aforementioned proprietary virtualization solution, had so many challenges. How does vSphere management measure up to RHEV Manager…
VMware vSphere: For all Mission Critical Workloads
While VMware vSphere also has a Windows-based manager — vCenter Server — it is not a single point of failure. The vSphere Client performs equally well when connected directly to a VMware ESX system to perform necessary management or configuration and various command-line utilities and scripts can be used without vCenter Server. Also note that VMware is not an operating system vendor and platform support is therefore based on customer demand and subject to the principles of free market economics.
Naturally, vCenter provides important configuration and management capabilities such as DRS and performance monitoring. If an environment cannot tolerate vCenter downtime, there are several methods that can be used to increase availability, from VMware HA, to MSCS clustering, to the high-end vCenter Server Heartbeat. Even if you don’t implement any of those measures and disaster strikes, it is relatively quick and easy to rebuild vCenter and bring live VMware ESX hosts back under management with zero impact on running VMs.
Dare to Compare
If you have not tried VMware vSphere 4, download your free 60-day evaluation with all Enterprise Plus features and capabilities today. I would say put it head-to-head against Red Hat Enteprise Virtualization, but since no evaluation version is available, that may be difficult.
If your datacenter needs the most reliable virtualization platform with the broadest support for guest operating systems — including Red Hat Enterprise Linux — and the best management capabilities in the industry, go with VMware vSphere.