Containers and VMs

In addition to OpenStack, RHV4 also supports container-based workloads, as exemplified, for example, in its support of RHEL Atomic Host as a guest system. The expansion or the configurability of policies for live migration is also new, offering benefits in particular for Monster VMs or live migration. For example, RHV4 allows fine tuning of live migration settings for a selected VM cluster level, such as the maximum bandwidth to use. Another new feature is that RHV can now deal with tags and labels that you can assign as a characteristic property to a VM or network.

RHV4 and Competitors

RHV leaves you with a mixed impression. In 2017, you are hardly likely to find companies that have not already gained experience with some kind of virtualization solution. RHV is thus mainly a strategic product both for Red Hat and for users; using it leaves the doors open in many directions, although the dice seem to have fallen in favor of OpenStack for the private cloud. Looking specifically at functions, RHV tends to focus on integration as a whole rather than maximizing virtualization functionalities. For example, the upcoming modeling of the Open vSwitch-based virtual networking stack is long overdue. Competitor VMware has for years offered fully modeled, software-defined Layer 2 switches that operate on par with Cisco in terms of APIs and features.

As another example, consider the ability of RHV4 to add tags and labels to objects – a function that competitors have also had for a long time. VMware also has more to offer in terms of resource management and prioritization, or performance monitoring. Whether the feature overkill in vSphere actually reflects the needs of enterprises in everyday life is a totally different question. However, what is irritating about RHV is that, in principle, no clear separation exists between the functions provided by the Linux kernel and other layers in RHEL that can typically only be configured at the command line. For open source specialists, this might be the norm, but in the context of Hyper-V and vSphere, it becomes difficult to compare capabilities, especially when some features advertised in RHV4 have received only a tech preview status.

Don't forget that the competitors (Hyper-V and vSphere) offer a powerful PowerShell-based Automation API. Die-hard Red Hat aficionados might turn up their noses at the mention of PowerShell, but it has developed into a reliable tool as an automation and management interface outside of the Linux world. If Red Hat is targeting VMware and Microsoft migrants with RHV4, things like this – when taking the fairly jaded look of the GUI and its missing functions into account – will be quite important. Of course, you have to remember that Ansible has a chic oVirt module. Dozens of VMs can be very easily cloned, preconfigured, and booted thanks to playbooks (Cloud-init).

Conclusions

In terms of costs, RHV4 is still a recommended product, especially when stability, enterprise capability, and performance leave little to complain about. Last but not least, RHV is possibly the better container platform than, for example, Windows Server 2016 Container Host or VMware because of its proximity to Linux and Docker.