Polished

Red Hat Virtualization (RHV) once set off to make professional virtualization at the enterprise level more affordable – in particular for small enterprises. However, the monetary barriers to entry are pretty high if you look at the market leader VMware. RHV4 is available both as a standalone product and as part of Red Hat Cloud Suite, which comprises OpenStack Platform, OpenShift, CloudForms, Satellite, and Ceph storage.

In conjunction with GlusterFS and Ceph storage solutions and integration of OpenShift containers and OpenStack Platform, RHV is a strategic product that can play an important role in transforming IT in many companies. Although still lagging well behind Microsoft, VMware, and Citrix, Red Hat likes to emphasize that its own virtualization solution is finding its way into many businesses via the OpenStack detour.

However, this fact was misunderstood by many companies. Not infrequently, small and medium-sized enterprises switched from VMware to OpenStack for classic virtual server workloads as a cost-effective alternative for vSphere. OpenStack, though, is far too complex as a private cloud solution. According to Red Hat, many such companies are now coming back to RHV after some painful experiences.

In this article, I describe the setup of a small test scenario that investigates whether the elaborate setups required in earlier versions of RHV have become easier, and I take a look at the most important new features, including faster performance, a new programming API, support for OpenStack and containers, the new dashboard for Red Hat Virtualization Manager (RHV-M), and the Cockpit-based option for running the Machine Manager more or less automatically as a hosted engine.

RHV4 Architecture

Setting aside the underlying data of the hypervisor, in which KVM, Xen, vSphere, and Hyper-V traditionally do not differ a great deal, integrated virtualization solutions are more about the trappings – that is, additional software features (live migration, clustering, etc.), interfaces to the outside, and ecosystem of partner products. What RHV4 offers all told can be gathered from the Feature Guide [1].

In terms of architecture, the solution remains unchanged, with the web-based RHV-M, which is based on the in-house JBoss Middleware as an application server, and the hypervisor nodes based either on Red Hat Virtualization Host (RHVH) or Red Hat Enterprise Linux (RHEL). Add to this, components such as the Simple Protocol for Independent Computing Environments (SPICE), which plays a central role in RHV, in particular as a virtual desktop infrastructure (VDI) solution or the Virtual Desktop Server Manager (VDSM) broker component.

All hypervisor nodes communicate with the management engine (ovirt-engine ) using a stack from Libvirt and VDSM, also known as the "oVirt host agent" in the context of oVirt. The guest systems use the "oVirt guest agents" written in Python to tell ovirt-engine, for example, which applications they are running, how much memory the applications need, or what IP address they have. In RHV, the hypervisor operation-optimized kernel with its minimal footprint is RHVH, and the management system, including the resource manager and management interface, is RHV-M. Currently RHV-M only runs on RHEL 7.2 and requires JBoss EAP 7, Java OpenJDK 8, and PostgreSQL 9.2.

Simplified Deployment

Rolling out RHV is far easier in version 4. As a minimum, you need one hypervisor node (but preferably three or more for cluster functions) that can be implemented on either the RHVH mini-footprint or RHEL. The former version was less popular with RHV insiders up to and including version 3.6 because of the heavily restricted shell. In RHV4, the RHVH footprint is now more convenient in this regard, although it has again shrunk compared with the previous version. After downloading the ISO image, you can complete the basic install for RHVH with Anaconda, which is a matter of a few mouse clicks. Next, sign up with the subscription manager on the Red Hat Content Delivery Network (CDN). An RHVH always automatically subscribes to a freely available RHVH entitlement. Now, you just need to integrate the rhel-7-server-rhvh-4-rpms repository:

$ subscription-manager repos --enable=rhel-7-server-rhvh-4-rpms

Registering the installation against the CDN is now a far more convenient experience than in the previous version; you can also do this in the new Cockpit user interface. To register the host, simply click on Tools | Subscriptions | Register System .

Installing RHV-M

You also need a Manager (RHEV-M) that is based on RHEL, either physically or as a virtual machine (VM). To install RHV (i.e., to "soup up" a standard RHEL machine and create an RHV-M host), you can use the complex engine-setup script. If you have bought an RHV subscription, you only need to subscribe to the corresponding channels with your RHEL VM (or a physical machine) to install the required RHEV packages. If you set up a fresh RHEL machine, first sign up as usual on the CDN and choose the appropriate subscription. The

subscription-manager list --available

command lists the available subscriptions. Now, attach the desired subscription via the pool ID by typing

subscription-manager attach --pool = pool_id

and subscribe to the required channels as follows:

$ subscription-manager repos --enable=rhel-7-server-rpms
$ subscription-manager repos --enable=rhel-7-server-supplementary-rpms
$ subscription-manager repos --enable=rhel-7-server-rhv-4.0-rpms
$ subscription-manager repos --enable=jb-eap-7-for-rhel-7-server-rpms

Finally, install the Manager with yum install rhevm.